research article thermal and cure kinetics of epoxy...

Hindawi Publishing CorporationAdvances in Materials Science and EngineeringVolume 2013 Article ID 391267 9 pageshttpdxdoiorg1011552013391267

Research ArticleThermal and Cure Kinetics of Epoxy Molding Compounds Curedwith Thermal Latency Accelerators

Chean-Cheng Su Chien-Huan Wei and Bo-Ching Li

Department of Chemical and Materials Engineering National University of Kaohsiung No 700 Kaohsiung University RoadNan-Tzu District Kaohsiung 811 Taiwan

Correspondence should be addressed to Chean-Cheng Su ccsunukedutw

Received 30 November 2012 Accepted 14 January 2013

Academic Editor Roham Rafiee

Copyright copy 2013 Chean-Cheng Su et al This is an open access article distributed under the Creative Commons AttributionLicense which permits unrestricted use distribution and reproduction in any medium provided the original work is properlycited

The cure kinetics and mechanisms of a biphenyl type epoxy molding compounds (EMCs) with thermal latency organophosphineacceleratorswere studied using differential scanning calorimetry (DSC)Although the use of triphenylphosphine-14-benzoquinone(TPP-BQ) and triphenylphosphine (TPP) catalysts in biphenyl type EMCs exhibited autocatalyticmechanisms thermal latency washigher in theTPP-BQcatalyst in EMCs than in theTPP catalyst in EMCsAnalyses of thermal characteristics indicated that TPP-BQis inactive at low temperatures At high temperatures however TPP-BQ increases the curing rate of EMC in dynamic and isothermalcuring experiments The reaction of EMCs with the TPP-BQ latent catalyst also had a higher temperature sensitivity compared tothe reaction of EMCs with TPP catalyst In resin transfer molding EMCs containing the TPP-BQ thermal latency accelerator areleast active at a low temperature Consequently EMCs have a low melt viscosity before gelation and the resins and filler are evenlymixed in the kneading process Additionally flowability is increased before the EMCs form a network structure in the moldingprocess The proposed kinetic model adequately describes curing behavior in EMCs cured with two different organophosphinecatalysts up to the rubber state in the progress of curing

1 Introduction

In IC design semiconducting chips have become largerwhile devices have become smaller Highly reliable plastic-encapsulated semiconductor packages are needed for ad-vanced electronic devices New epoxy molding compounds(EMCs) for encapsulatingmicroelectronic devices are neededin the near future because halogen-containing flame retar-dants and antimony oxide flame retardant synergists whichare widely used in present-day molding compounds maybe environmentally hazardous In typical green moldingcompounds flame retardants (eg phosphorus-containingcompounds nitrogen-containing compoundsmetal hydratemetal oxide inorganic filler and resins with high CH ratios)have generally replaced the conventional halogen-containingflame retardants and antimony oxide flame retardants used inEMCs [1 2] Notably EMC with biphenyl resins and highlyloaded fillers can retard flammability and is a green materialTo produce reliable packaging materials for microelectronic

devices a highly loaded filter with specific characteristics isneeded high flame retardation high thermal resistance highmoisture resistance favorable mechanical properties and alow thermal expansion coefficient of EMC [3 4]

Catalysts are often used to accelerate curing in epoxysystems such as EMCs epoxy prepreg epoxy powder coatingand so forth Choosing the appropriate type and amount ofcatalyst is important in epoxy formulations In the literature[5ndash8] reports of catalysts for curing epoxy resin can beclassified as Lewis bases and Lewis acids Lewis bases containan unshared pair of electrons in an outer orbit and tendto react with areas of low electron density Their manyapplications include nucleophilic catalytic curing agents forepoxy homopolymerization cocuring agents for primaryamines polyamides and amidoamines and catalysts foranhydrides Tertiary amines and imidazoles are the mostwidely used nucleophilic catalysts In contrast Lewis acidswhich have an empty outer orbit tend to react with areas ofhigh electron density Complexation of boron trihalides with

2 Advances in Materials Science and Engineering

amines enhances the curing action Reactivity depends onthe selected halide and amine Boron trifluoride monoethy-lamine is a typical catalyst

EMCs typically include a curing accelerator (catalyst)which accelerates the curing of resin and increases the num-ber of molding cycles for mass production Storage stabilityphysical characteristics and reliability of the encapsulatedsemiconductors diverge widely with the species of curingaccelerator used Capable of controlling initial polymer-ization or curing thermally latent catalysts are used inpackaging In EMCs typical accelerators are imidazole [2 9]amines [10ndash12] organophosphine [1 10] urea derivatives[13 14] or Lewis bases and their organic salts [15 16]However most accelerators tend to reduce the pot life ormoldability of molding materials owing to their ability toinitiate reactions at extremely low temperatures Thereforean effective hardening accelerator must have a thermallatency that promotes the rapid curing of resins when heatedto a particular temperature in contrast latent acceleratorsare inert at low temperatures [1 17] Exactly how curingaccelerators affect the physical and electrical characteristicsof EMC have been thoroughly studied [16ndash19] In theseworks EMCs with triphenyl phosphine (TPP) have optimalphysical properties andparticularly good electrical propertiesunder high humidity condition when cured subsequentlyimproving the reliability of the encapsulated semiconductorsHowever the curing reaction of the EMC is significantlyaccelerated at a low temperature in addition a high meltviscosity duringmolding EMC that contains TPP has a shortpot lifeTherefore an improved organophosphine acceleratorwith thermally latent characteristics is urgently required forusing in EMCs Notably the EMCs must have superiorstorage stability latent reactivity and low melting viscosityduring molding

The Lewis base catalyst triphenylphosphine-14-benzo-quinone (TPP-BQ) is the thermally latent catalyst used inthe epoxy molding compounds which can control initialpolymerization or curing and are used in packaging [1 20] Aprevious study found that TPP-BQ accelerated the reaction ofEMCs more than TPP did at high temperatures in additionEMCs containing TPP-BQ were relatively inert at a lowtemperature [20] In the TPP-BQ complex the resonance ofBQ increases the stability of the complex and reduces theactivity of lone electron pairs Nucleophilic attack by theorganophosphine accelerators appears to open the epoxidewhich is suppressed in the organophosphine accelerators-cured EMC at a low temperature The molding compoundscontaining TPP-BQ exhibited excellent moldability and stor-age stability characteristics Moreover they were appropriatefor transfer molding owing to their excellent latent reac-tivity Additionally molding compounds containing TPP-BQ had an extremely low melt viscosity before gelationIn low-viscosity green epoxy molding compounds 441015840-Diglycidyloxy-331015840551015840-tetramethyl biphenyl epoxy providesgood adhesion high toughness and high filler loadingBecause of its very low reaction rate however an EMC basedon this biphenyl type epoxy is unsuitable for molding Thiswork synthesized a new organophosphine thermally latentaccelerator TPP-BQ for use in high filler-loadedEMCs based

Table 1 Formulation of epoxy molding compounds

Composition Raw materials Parts byweight

Epoxy 441015840-diglycidyloxy-331015840551015840-tetramethyl biphenyl 90

Br-epoxy Diglycidyl ether of brominatedbisphenol A 10

Hardener Phenol-aralkyl resin 88

AcceleratorTriphenylphosphine (TPP) ortriphenylphosphine-14-benzoquinone(TPP-BQ)

3

Filler Fused silica 1510Couplingagent Glycidoxypropyltrimethoxysilane 7

Release agent Ethyleneglycol ester of montanic acid 7Colorant Carbon black 4

on biphenyl-type epoxy The objective of this study was tocharacterize the reactivity and cure behavior of EMCs curedwith thermal latency catalysts TPP-BQ and TPP A kineticmodel was used to show how a thermal latency catalyst affectscuring in an EMC

2 Experimental

21 Materials and Sample Preparation Table 1 presents theformulation of the EMCThe epoxy resins used in the experi-ments were 441015840-diglycidyloxy-331015840551015840-tetramethyl biphenyl(JER Co YX-4000H EW = 192 geq) and diglycidyl etherof brominated bisphenol A (Sumitomo Co ESB 400) Thehardener was phenol-aralkyl resin (Mitsui Chemical IncXLC-2L OH EW = 175 geq) Scheme 1 shows the chemicalstructure of the epoxy and the hardener

The TPP catalyst was obtained from Hooko Co TheTPP-BQ catalyst was synthesized by the authors and wasidentified using Fourier transform infrared spectroscopy(FTIR) and nuclear magnetic resonance (NMR) [20] Thechemical structure of the catalysts is described in Scheme 2

The filler was fused silica with a mean particle size(D50) of 20120583m (Tatsumori Co) The coupling agent was

glycidoxypropyltrimethoxysilane (Shin-Etsu Chemical Co)The release agent was ethylene glycol ester of montanic acid(Hoechst Co) The colorant was carbon black (Cabot CoCM 800)

The materials were weighed out in the ratios given inTable 1 and thoroughly kneaded using a two-roll mill withthe cold roller operated at 15∘C and the hot roller operated at120∘C After mixing EMC was cooled and pulverized Eachsample was then stored in a refrigerator at 4∘C

22 Instruments Calorimetric measurements were madeusing a differential scanning calorimeter (DSC) (Perkin-Elmer DSC-7) equipped with an intracooler Isothermaland dynamic-heating experiments were performed at a50mLmin nitrogen flow In dynamic curing the sample was

Advances in Materials Science and Engineering 3

OO O CH

O

H2C CH2 CH2 CH2 CH2

CH3

CH3

CH3

CH3

(a)

(b)

OH OH OH

H2C H2C H2C H2C

119899

Scheme 1 The chemical structure of the (a) 441015840-diglycidyloxy-331015840551015840-tetramethyl biphenyl epoxy and (b) phenol-aralkyl resin

3

P

3

P+ sdot minusO O

(a)

(b)

Scheme 2 The chemical structure of the (a) TPP and (b) TPP-BQ

heated at a rate of 10∘Cmin from 0∘C to 250∘C The isother-mal curing reaction was performed at five temperatures(130 150 165 175 and 185∘C) The reaction was consideredcomplete when the isothermal DSC thermogram stabilized atthe baseline level which generally required approximately 1 hAt the end of the reaction the total area under the exothermcalculated according to the extrapolated baseline was used tocalculate the isothermal heat of curing Δ119867Io (Jg

minus1) After thecuring reaction was completed in the calorimeter the samplewas cooled to 40∘C After curing the samples were scannedat 10∘Cmin from 40∘C to 250∘C to measure residual heatfrom the reactionΔ119867

119877(Jgminus1)The total heat of curing (Δ119867

119879)

was calculated by summing the isothermal heat (Δ119867Io) andthe residual heat (Δ119867

119877) from the reactions The isothermal

conversion at time 119905 was defined as 120572119868(119905) = Δ119867

119868(119905)Δ119867

119879

The obtained 119879119892values were taken as the temperatures of the

onset of glass transition (at which the specific heat changed)in the DSC thermograms

Morphology studies of the cured epoxy molding com-pounds were performed by scanning electron microscope(Hitachi S-4800 field-emission SEM) The fracture sampleswere polished and coatedwith gold by vapor deposition usinga vacuum sputter

23 Kinetic Analysis A general equation for the autocatalyticcure reactions of many epoxy systems is as follows [21ndash25]

119903 =119889120572

119889119905= (1198961+ 1198962120572119898) (1 minus 120572)

119899 (1)

where 120572 is the extent of conversion 119903 is the rate of thereaction 119896

1and 119896

2are the apparent rate constants and m

and n are the kinetic exponents of the reactions The kineticconstants 119896

1and 119896

2are assumed to be in Arrhenius form

[22ndash24 26]

119896119894= 119860119894exp(minus119864119886119894

119877119879) (2)

where 119860119894is the preexponential constant 119864

119886119894is the activation

energy 119877 is the gas constant and 119879 is the absolute tempera-ture The ln 119896

119894can be plotted versus 1119879 and the activation

energies are obtained in the equation Equation (1) revealsthat constant 119896

1can be calculated from an initial reaction

rate in which 120572 approximates 0 Additionally (1) providesan initial estimate of the reaction order 119899 by performing thefollowing modification

ln(119889120572119889119905) = ln (119896

1+ 1198962120572119898) + 119899 ln (1 minus 120572) (3)

Except for the initial region a plot of ln(119889120572119889119905) versus ln(1 minus120572) is expected to be linear and to have a slope of 119899 Furtherrearrangement of (1) gives

ln [ 119889120572119889119905(1 minus 120572)

119899minus 1198961] = ln 119896

2+ 119898 ln120572 (4)

The first term in (4) can be determined from the pre-viously estimated values for 119896

1and 119899 A plot of the left-

hand term in (4) versus ln(120572) is expected to yield a straightline The slope and intercept can then be used to estimatethe reaction order 119898 and the autocatalytic kinetic constant1198962 respectively The described procedure is applicable for

obtaining the preliminary kinetic parameters from the firsttrial However an iterative procedure is required to yieldmore values Equation (4) can also be reformulated as

ln(119889120572119889119905) minus ln (119896

1+ 1198962120572119898) = 119899 ln (1 minus 120572) (5)

where 1198962 119898 and 119899 are estimated according to the stated

procedures the left-hand terms in (5) can be plotted againstln(1 minus 120572) and a new value of the reaction order 119899 is checkedagainst the one obtained earlierThe same iterative procedurecan be repeated until the values of 119898 and 119899 converge towithin a deviation of 1

3 Result and Discussion

31 Analyzing Curing kinetics for EMCs withThermal LatencyCatalyst After the EMCs with TPP and TPP-BQ catalystswere cured at isothermal temperatures of 130 150 165175 and 185∘C the above models were used for kineticanalysis Figures 1 and 2 plot the curing rate curves forEMCs catalyzed by TPP-BQ and TPP respectively at fiveisothermal temperatures Figure 1 shows that the curves aredistinctly autocatalytic with the maximum rates occurring30 19 12 10 and 08min after the start of the reactionat isothermal reaction temperatures of 130 150 165 175


1 100

40

80

120

160

Log(time) (min)

Rate

(minminus1)

TPP-BQ130∘C

150∘C165∘C

175∘C185∘C

Figure 1 Plots of the reaction rate versus time for TPP-BQ-curedEMCs at isothermal temperatures

and 185∘C respectively Figure 2 clearly shows that these ratecurves are autocatalytic The maximum rates were observedat 30 22 19 18 and 17min after the start of the reactionat isothermal reaction temperatures of 130 150 165 175 and185∘C respectively The result shown in these figures demon-strates that the mechanism of the TPP-BQ-cured EMCsand that of TPP-cured EMCs has the same autocatalyticnature However the reaction rate of the TPP-BQ-curedEMC is clearly enhanced at high temperature and restrainedat low temperature since the maximum rate increases withreaction temperature in the molding compounds The epoxyreaction rate revealed a similar effect in the epoxy moldingcompounds with TPP catalyst Figures 3(a) and 3(b) show thetimes of the maximum rate and curing time respectively inthe epoxy molding compounds cured with organophosphineaccelerators In the epoxy molding compounds cured withcatalysis with organophosphine accelerators the times ofthe maximum rate and curing time depended on both thereaction temperature and the organophosphine acceleratortype Figure 3(a) indicates that EMCs catalyzed by TPP hada shorter time of the maximum rate than that of EMCscatalyzed by TPP-BQ at a low temperature (130∘C) Con-versely EMCs catalyzed by TPP-BQ had a shorter time ofthe maximum rate than that of EMCs catalyzed by TPPat high temperatures (150 165 175 and 185∘C) The samechange was also observed in the curing time in EMCscatalyzed by organophosphine accelerators (Figure 3(b)) Atlow temperature (130∘C) the curing rate of EMCs containingTPP exceeded that of EMCs containing TPP-BQ at hightemperatures (150 165 175 and 185∘C) however EMCs

0

50

100

150

200

250

1 10Log(time) (min)

TPP130∘C

150∘C165∘C

175∘C185∘C

Rate

(minminus1)

Figure 2 Plots of the reaction rate versus time for TPP-cured EMCsat isothermal temperatures

containing TPP-BQ are cured at a higher rate comparedto EMCs containing TPP The EMCs catalyzed by TPP-BQaccelerator also had a rapid rate of curing at the moldingtemperatures used specifically for IC encapsulation (119879 =175ndash185∘C) These findings indicate that TPP is better thanTPP-BQ as a catalyst for curing EMCs at low temperatures Athigh temperatures however the acceleration in reaction timewas larger in EMCS cured with TPP-BQ than in EMCS curedwith TPP and EMCs containing TPP-BQwere relatively inertat a low temperature Notably the general biphenyl EMCtransfer molding temperatures used for IC encapsulationrange from 175 to 185∘C During molding EMCs containingTPP-BQ are least active before the temperature reachesthe molding temperature The experimental results indicatethat TPP-BQ is superior to TPP as a latency accelerator inbiphenyl type EMCs

Table 2 presents themean residual heat of reaction (Δ119867119877)

isothermal heat of reaction (Δ119867Io) total heat of curing(Δ119867119879) and isothermal conversion (120572

119868) Note that the heat

from reactions in the EMCs was calculated based on the netweight of the biphenylphenol-aralkyl resin in the moldingcompounds without considering the weight of fillers in theEMCs In this work the total heats of curing (Δ119867Io + Δ119867119877)were independent of the organophosphine accelerator typeThe mean value was 184 Jgminus1 At a 130∘C curing temperaturethe table also shows that the isothermal conversions (120572

119868)

were 929 and 934 for EMCs containing TPP and TPP-BQ respectively which indicated that the reactions wereincomplete at a low temperature However the isothermalconversions (120572

119868) were 100 when the EMCs were completely


Table 2 Heats of reaction of epoxy molding compounds catalyst byTPP and TPP-BQ

Accelerators 119879 (∘C) Δ119867Io(J gminus1)

Δ119867119877

(J gminus1)Δ119867119879

(J gminus1) 120572I ()

130 170 12 182 934150 184 0 184 100

TPP-BQ 165 183 0 183 100175 185 0 185 100185 186 0 186 100130 171 13 184 929150 183 0 183 100

TPP 165 184 0 184 100175 183 0 183 100185 185 0 185 100

cured at high temperatures (150ndash185∘C)The table also showsthat the ultimate conversion (120572

119868) for EMCs catalyzed by

organophosphine accelerators increased from 93 to 100as cure temperature increased from 130 to 185∘C whichindicate that the reactions would be expected to reach dif-fusion control (rubber state) regions at progressively higherconversions as reaction temperatures increase FurthermoreEMCs containing TPP and TPP-BQ accelerators not only hadsimilar reaction rate curves but they also had similar Δ119867and 120572

119868 which suggests EMCs containing TPP and TPP-BQ

accelerators have a similar reaction mechanism

32 Autocatalytic Model Analysis The molding compounddata were then analyzed using the proposed autocatalyticmechanism The kinetic parameters were determined usingthe above procedures For the kinetic constants 119896

1and 119896

2

two activation energies Δ1198641and Δ119864

2 could be obtained

by plotting ln 1198961and ln 119896

2 respectively versus 1119879 Figure 4

shows the plots for ln 1198961and ln 119896

2versus 1119879 fromwhich the

activation energies were determined for the EMCs Table 3lists the rate constants obtained after considerable iterationand graphic procedures Reaction orders 119898 and 119899 approxi-mated 05 and 14 respectively and did not substantially varyamong EMCs with different organophosphine acceleratorsFor the TPP-BQ-catalysis EMCs the 119864

1198861and 119864

1198862values

obtained in this studywere 152 and 116 kJmolminus1 respectivelyIn contrast the 119864

1198861and 119864

1198862values obtained for the TPP-

catalysis EMCs were 114 and 96 kJmolminus1 respectively Asactivation energy increased the temperature sensitivity of thereaction increased Restated for a large activation energya temperature increase of only a few degrees significantlyincreased 119896 subsequently increasing the reaction rate Incomparison to TPP catalyst-cured EMCs TPP-BQ catalyst-cured EMCshad higher activation energies Further since thedifference in Δ119864

1198861(38 kJmolminus1) between TPP-BQ catalyst-

cured EMCs and TPP catalyst-cured EMCs was larger thanthe difference inΔ119864


cured EMCs and TPP catalyst-cured EMCs the increasedreaction rate might be associated with 119896

1 Since 119896

1governs

the early stage-autocatalytic reaction and since 1198962affects

120 140 160 180 2000

2

4

6

Temperature (∘C)

Tim

e of m

axim

um ra

te (m

in)

(a)

0

10

20

30

120 140 160 180 200Temperature (∘C)

Curin

g tim

e (m

in)

TPPTPP-BQ

(b)

Figure 3 Curing times of organophosphine accelerators-curedEMCs at isothermal temperatures (a) times of the maximum rateand (b) curing times

the reaction after the initial autocatalytic stage the rate ofincrease at high temperatures in EMCs with TPP-BQ catalystshould be expected to accelerate in the initial stage of thereaction [26]

The autocatalytic kinetic model and the rate constantsobtained (listed in Table 3) were used to calculate empiricalcurves of conversion versus time for the organophosphineaccelerator-cured EMCs at all five isothermal cure temper-atures Figures 5 and 6 show that the empirical conversion


Table 3 Kinetic parameters for epoxy molding compounds catalyst by TPP and TPP-BQ

Accelerator 119879 (∘C) 119898 1198991198961

(minminus1)1198962

(minminus1)1198641198861

(kJmolminus1)1198641198862

(kJmolminus1) ln1198601

ln1198602

130 04 13 66 128150 04 14 65 617

TPP-BQ 165 05 10 202 1294 183 116 165 133175 06 10 398 2005185 13 11 1148 3308130 05 13 126 316150 05 13 165 1029

TPP 165 06 14 455 1893 126 96 129 123175 06 15 731 2910185 05 15 1109 4769

0005 0006 0007 0008

0

4

8

ln1198961

(minminus1)

1119879 (1K)

(a)

0005 0006 0007 00080

2

4

6

8

10

ln1198962

(minminus1)

1119879 (1K)

TPPTPP-BQ

(b)

Figure 4 Kinetic analysis for organophosphine accelerators-cured EMCs in an autocatalysed reaction (a) plots of ln 1198961against 1119879 and (b)

plots of ln 1198962against 1119879 respectively

curves fit the experimental data quite well until the cure reac-tions progress to the rubber state for TPP-BQ-cured EMCsand TPP-cured EMCs Epoxy resins are thermosets whoseindividual chains have been chemically linked by covalentbonds during isothermal reaction Once formed these cross-linked networks resist heat softening and creep Generally arubber-like state may be defined as an amorphous and cross-linked polymer above its glass transition temperature (119879

119892)

Following cross linking flow of one molecule past anotheris suppressed in organophosphine accelerator-cured EMCsin the rubber state In the work a similar 119879

119892value (120∘C)

was obtained in fully cured TPP-BQ-cured EMCs and TPP-cured EMCs Apparently the model satisfactorily describesthe kinetic well However diffusion control in the rubber state

affects the predictive accuracy of the model This indicatesthat the cure kinetics for organophosphine accelerator-curedEMCs in the later stage are indeed subject to diffusion controlin the rubber state In the organophosphine accelerator-cured EMCs the predictability of the model at high curetemperatures is better than that at low cure temperatures

33 Comparison of TPP-BQ-Cured EMCs with TPP-CuredEMCs Figures 7 and 8 show the rate versus conversioncurves for organophosphine accelerator-cured EMCs at fiveisothermal cure temperatures (130 150 165 175 and 185∘C)Figure 7 shows the similar trends in cure reaction ratesobserved in TPP-BQ-cured EMCs at five cure temperaturesThe maximum rates approximated 33 and 17 of the


0 10 20 300

20

40

60

80

100

Time (min)

Con

vers

ion

()

TPP-BQ

130∘C150∘C165∘C

175∘C185∘C

Figure 5 Comparison between the autocatalyticmodel and data forTPP-BQ-cured EMCs at isothermal temperatures

0 4 8 12 16 200

20

40

60

80

100

Time (min)

Con

vers

ion

()

TPP130∘C150∘C

165∘C

175∘C185∘C

Figure 6 Comparison between the autocatalyticmodel and data forTPP-cured EMCs at isothermal temperatures

conversion at high temperatures (165 175 and 185∘C) and atlow temperatures (130 and 150∘C) respectively In contrastthe trends in cure reaction rates of TPP-cured EMCs aresimilar at five cure temperatures and the maximum rateapproximated 20 and 10 of the conversion at high tem-peratures (165 175 and 185∘C) and at low temperatures (130

0 20 40 60 80 1000

40

80

120

160

200

Conversion ()

Rate

(minminus1)

TPP-BQ130∘C150∘C165∘C

175∘C185∘C

Figure 7 Plots of the reaction rate versus conversion for TPP-BQ-cured EMCs at isothermal temperatures

and 150∘C) respectively (Figure 8) In TPP-BQ accelerator-cured biphenyl EMCs the reaction of the biphenylphenol-aralkyl resin at higher conversions still maintained a high rateof progress in the cure reaction In contrast the reaction rateof TPP accelerator-cured EMCs was high in the early stageand low in the later stage After 70 conversion TPP-BQ-cured EMCs had a higher rate than TPP accelerator-curedEMCs did at the five cure temperatures shown in the figuresIn resin transfer molding EMC flowed through the moldingpart until the compound was transformed into gel If thecuring rate of EMC was too fast the melting EMC wouldhave increased the viscosity and decreased the flowabilityin the mold Both viscosity and flowability are generallyrelated to the degree of reaction of EMC during molding Inmicroelectronic packaging the acceleration of the reactionof EMC containing TPP-BQ is weak at low temperatures butstrong at high temperatures during thermal latency curingThe experimental results suggest that the TPP-BQ acceleratoris an ideal thermal latency accelerator for curing EMCs

34Morphology of EMCswithHigh Filler Content TheEMCswith high filler contents are accelerated by organophosphineaccelerators TPP-BQ and TPP which provide excellentflowability in the molding process In the molding processmelting EMCs with high flowability easily fill the wholemould before hardening Figures 9(a) and 9(b) show themorphology of the fractured surface of EMCs with 88wtcontent of silica accelerated by TPP-BQ and TPP acceleratorrespectively and cured at 175∘C In Figure 9(a) the spherulicsilca of varying sizes is well distributed and packed closely


0 20 40 60 80 1000

100

200

300

Conversion ()

Rate

(minminus1)

TPP130∘C150∘C165∘C

175∘C185∘C

Figure 8 Plots of the reaction rate versus conversion for TPP-curedEMCs at isothermal temperatures

on the fractured surface of the EMC in the cured sampleBecause TPP-BQ-cured EMCs have a low melt viscositybefore gelation as well as least active at low temperaturesthe organic matrixes and filler are easily and well mixed inthe kneading process in addition the flowability of EMC isincreased in the molding process In contrast the silica isless evenly distributed and is loosely packed in the fracturedsurface of the TPP-cured EMC shown in Figure 9(b) Thesilica is not well mixed in the TPP-cured EMC because theEMC had a high reaction rate and a high viscosity in thekneading process

4 Conclusions

In isothermal curing TPP is a more rapid catalyst comparedto TPP-BQ for curing EMCs at low temperatures HoweverTPP-BQ accelerated the reaction of EMCs more than TPPdid at high temperatures and EMCs containing TPP-BQwere relatively inert at a low temperature An autocatalyticmechanism was observed for organophosphine accelerator-cured EMCs Kinetic parameters for the EMCs with TPP-BQ and TPP accelerator were obtained and the proposedkinetic model accurately described the cure behavior oforganophosphine accelerator-cured EMCs up to the rubberstate Although the reaction mechanism for both TPP-BQ-cured EMCs and TPP-cured EMCs was similar thermallatency was superior in the TPP-BQ-cured EMCsThemodelshowed that the increased temperature sensitivity resultedfrom the larger activation energy in EMCs with TPP-BQaccelerator Based on the observations in this study the rateincrease at high temperatures in EMCs with TPP-BQ catalyst

(a)

(b)

Figure 9 Morphology of organophosphine accelerators-curedepoxy molding compounds (a) TPP-BQ-cured EMC and (b) TPP-cured EMC respectively

should be pronounced in the initial stage of the reactionFurthermore in TPP-BQ accelerator-cured biphenyl EMCsthe reaction of the EMC at high conversions remained highas the cure reaction progressed during the EMC transfermolding process In microelectronic packaging the accel-eration of the reaction of EMC containing thermal latencyTPP-BQ accelerator correlates positively with temperatureThis suggests that the TPP-BQ accelerator is an ideal thermallatency accelerator for curing EMCs

Acknowledgments

This study is sponsored by the National Science Council ofthe Taiwan for financially supporting this research underContract no NSC 100-2221-E-390-006-MY2 The authorsdeclare no competing financial interest

References

[1] J H Ryu K S Choi and W G Kim ldquoLatent catalyst effectsin halogen-free epoxy molding compounds for semiconductorencapsulationrdquo Journal of Applied Polymer Science vol 96 no6 pp 2287ndash2299 2005


[2] G H Hsiue Y L Liu and H H Liao ldquoFlame-retardant epoxyresins an approach from organic-inorganic hybrid nanocom-positesrdquo Journal of Polymer Science A vol 39 no 37 pp 986ndash996 2001

[3] N Kinjo M Ogata K Nishi and A Kaneda ldquoEpoxy moldingcompounds as encapsulation materials for microelectronicdevicesrdquoAdvanced Polymer Science vol 88 no 1 pp 1ndash48 1989

[4] Y Nakamura M Yamaguchi A Tanaka andM Okubo ldquoTher-mal shock test of integrated circuit packages sealed with epoxymoulding compounds filled with spherical silica particlesrdquoPolymer vol 34 no 15 pp 3220ndash3224 1993

[5] H F Mark Encyclopedia of Polymer Science and TechnologyJohn Wiley amp Sons New York NY USA 3rd edition 2007

[6] A Romanchick and J F Geibel ldquoSynthesis of solid rubber-modified epoxy resinsrdquo Organic Coatings and Applied PolymerScience Processing vol 46 no 2 pp 410ndash415 1982

[7] A M Tomuta X Ramis and F Ferrando ldquoThe use of dihy-drazides as latent curing agents in diglycidyl ether of bisphenolA coatingsrdquo Progress in Organic Coatings vol 74 no 1 pp 59ndash66 2012

[8] I Glavchev K Petrova and I Devedjiev ldquoDetermination ofthe rate of cure of epoxy resinmaleic anhydrideLewis acidsrdquoPolymer Testing vol 21 no 1 pp 89ndash91 2002

[9] C SWang and C Kwag ldquoCure kinetics of an epoxy-anhydride-imidazole resin system by isothermal DSCrdquo Polymers andPolymer Composites vol 14 no 5 pp 445ndash454 2006

[10] Z Ma and J Gao ldquoCuring kinetics of o-cresol formaldehydeepoxy resin and succinic anhydride system catalyzed by tertiaryaminerdquo Journal of Physical Chemistry B vol 110 no 25 pp12380ndash12383 2006

[11] T Nakaya M Shimbo and T Takahama ldquoEffects of tertiaryamine accelerators on curing of epoxide resinsrdquo Journal ofPolymer Science B vol 24 no 9 pp 1931ndash1941 1986

[12] A Srivastava N Pal S Agarwal and J S P Rai ldquoKinetics andmechanism of esterification of epoxy resin with methacrylicacid in the presence of tertiary aminesrdquo Advances in PolymerTechnology vol 24 no 1 pp 1ndash13 2005

[13] H Niino S Noguchi Y Nakano and S Tazuke ldquoAminimide ashardenercuring promotor for one part epoxy resin composi-tionrdquo Journal of Applied Polymer Science vol 27 no 7 pp 2361ndash2368 1982

[14] XD LiuMKimura A Sudo andT Endo ldquoAccelerating effectsof N-aryl-N1015840N1015840-dialkyl ureas on epoxy-dicyandiamide curingsystemrdquo Journal of Polymer Science A vol 48 no 23 pp 5298ndash5305 2010

[15] P N Son and C D Weber ldquoSome aspects of monuron-accelerated dicyandiamide cure of epoxy resinsrdquo Journal ofApplied Polymer Science vol 17 no 5 pp 1305ndash1313 1973

[16] M Kobayashi F Sanda and T Endo ldquoSubstituent effectof (triphenylphosphinemethylene)boranes on latent catalyticactivity for polyaddition of bisphenol a diglycidyl ether withbisphenol a model system of epoxy-novolac resinrdquo Macro-molecules vol 35 no 2 pp 346ndash348 2002

[17] S HanWG KimH G Yoon and T JMoon ldquoCuring reactionof biphenyl epoxy resin with different phenolic functionalhardenersrdquo Journal of Polymer Science A vol 36 no 5 pp 773ndash783 1998

[18] W G Kim J Y Lee and K Y Park ldquoCuring reaction of o-cresolnovolac epoxy resin according to hardener changerdquo Journal ofPolymer Science A vol 31 no 3 pp 633ndash639 1993

[19] M Ogata N Kinjo S Eguchi H Hozoji T Kawata and HSashima ldquoEffects of curing accelerators on physical propertiesof epoxy molding compound (EMC)rdquo Journal of Applied Poly-mer Science vol 44 no 10 pp 1795ndash1805 1992

[20] C C Su C H Wei and C C Yang ldquoElucidating howadvanced organophosphine accelerators affect molding com-poundsrdquo Industrial amp Engineering Chemistry 2013

[21] W G Kim and J H Ryu ldquoPhysical properties of epoxymoldingcompound for semiconductor encapsulation according to thecoupling treatment process change of silicardquo Journal of AppliedPolymer Science vol 65 no 10 pp 1975ndash1982 1997

[22] C C Su and E M Woo ldquoCure kinetics and morphologyof amine-cured tetraglycidyl-441015840-diaminodiphenylmethaneepoxy blends with poly(ether imide)rdquo Polymer vol 36 no 15pp 2883ndash2894 1995

[23] C C Su Y P Huang and E M Woo ldquoCuring kineticsand reaction-induced homogeneity in networks of poly(4-vinyl phenol) and diglycidylether epoxide cured with aminerdquoPolymer Engineering and Science vol 45 no 1 pp 1ndash10 2005

[24] C C Su and E MWoo ldquoDiffusion-controlled reaction mecha-nisms during cure in polycarbonate-modified epoxy networksrdquoJournal of Polymer Science B vol 35 no 13 pp 2141ndash2150 1997

[25] K C Cole J J Hechler and D Noel ldquoA new approach tomodeling the cure kinetics of epoxy amine thermosettingresins 2 Application to a typical system based on bis[4-(diglycidylamino)phenyl]methane and bis(4-aminophenyl)sulfonerdquoMacromolecules vol 24 no 11 pp 3098ndash3110 1991

[26] H S Fogler Essentials of Chemical Reaction Engineering Pear-son Education New York NY USA 4th edition 2011

Submit your manuscripts athttpwwwhindawicom

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CorrosionInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Polymer ScienceInternational Journal of



CeramicsJournal of


CompositesJournal of

NanoparticlesJournal of



International Journal of

Biomaterials


NanoscienceJournal of

TextilesHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of

NanotechnologyHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

CrystallographyJournal of


The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014


CoatingsJournal of

Advances in

Materials Science and EngineeringHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Smart Materials Research



MetallurgyJournal of


BioMed Research International

MaterialsJournal of


Nano

materials


Journal ofNanomaterials


amines enhances the curing action Reactivity depends onthe selected halide and amine Boron trifluoride monoethy-lamine is a typical catalyst

EMCs typically include a curing accelerator (catalyst)which accelerates the curing of resin and increases the num-ber of molding cycles for mass production Storage stabilityphysical characteristics and reliability of the encapsulatedsemiconductors diverge widely with the species of curingaccelerator used Capable of controlling initial polymer-ization or curing thermally latent catalysts are used inpackaging In EMCs typical accelerators are imidazole [2 9]amines [10ndash12] organophosphine [1 10] urea derivatives[13 14] or Lewis bases and their organic salts [15 16]However most accelerators tend to reduce the pot life ormoldability of molding materials owing to their ability toinitiate reactions at extremely low temperatures Thereforean effective hardening accelerator must have a thermallatency that promotes the rapid curing of resins when heatedto a particular temperature in contrast latent acceleratorsare inert at low temperatures [1 17] Exactly how curingaccelerators affect the physical and electrical characteristicsof EMC have been thoroughly studied [16ndash19] In theseworks EMCs with triphenyl phosphine (TPP) have optimalphysical properties andparticularly good electrical propertiesunder high humidity condition when cured subsequentlyimproving the reliability of the encapsulated semiconductorsHowever the curing reaction of the EMC is significantlyaccelerated at a low temperature in addition a high meltviscosity duringmolding EMC that contains TPP has a shortpot lifeTherefore an improved organophosphine acceleratorwith thermally latent characteristics is urgently required forusing in EMCs Notably the EMCs must have superiorstorage stability latent reactivity and low melting viscosityduring molding

The Lewis base catalyst triphenylphosphine-14-benzo-quinone (TPP-BQ) is the thermally latent catalyst used inthe epoxy molding compounds which can control initialpolymerization or curing and are used in packaging [1 20] Aprevious study found that TPP-BQ accelerated the reaction ofEMCs more than TPP did at high temperatures in additionEMCs containing TPP-BQ were relatively inert at a lowtemperature [20] In the TPP-BQ complex the resonance ofBQ increases the stability of the complex and reduces theactivity of lone electron pairs Nucleophilic attack by theorganophosphine accelerators appears to open the epoxidewhich is suppressed in the organophosphine accelerators-cured EMC at a low temperature The molding compoundscontaining TPP-BQ exhibited excellent moldability and stor-age stability characteristics Moreover they were appropriatefor transfer molding owing to their excellent latent reac-tivity Additionally molding compounds containing TPP-BQ had an extremely low melt viscosity before gelationIn low-viscosity green epoxy molding compounds 441015840-Diglycidyloxy-331015840551015840-tetramethyl biphenyl epoxy providesgood adhesion high toughness and high filler loadingBecause of its very low reaction rate however an EMC basedon this biphenyl type epoxy is unsuitable for molding Thiswork synthesized a new organophosphine thermally latentaccelerator TPP-BQ for use in high filler-loadedEMCs based

Table 1 Formulation of epoxy molding compounds

Composition Raw materials Parts byweight

Epoxy 441015840-diglycidyloxy-331015840551015840-tetramethyl biphenyl 90

Br-epoxy Diglycidyl ether of brominatedbisphenol A 10

Hardener Phenol-aralkyl resin 88

AcceleratorTriphenylphosphine (TPP) ortriphenylphosphine-14-benzoquinone(TPP-BQ)

3

Filler Fused silica 1510Couplingagent Glycidoxypropyltrimethoxysilane 7

Release agent Ethyleneglycol ester of montanic acid 7Colorant Carbon black 4

on biphenyl-type epoxy The objective of this study was tocharacterize the reactivity and cure behavior of EMCs curedwith thermal latency catalysts TPP-BQ and TPP A kineticmodel was used to show how a thermal latency catalyst affectscuring in an EMC

2 Experimental

21 Materials and Sample Preparation Table 1 presents theformulation of the EMCThe epoxy resins used in the experi-ments were 441015840-diglycidyloxy-331015840551015840-tetramethyl biphenyl(JER Co YX-4000H EW = 192 geq) and diglycidyl etherof brominated bisphenol A (Sumitomo Co ESB 400) Thehardener was phenol-aralkyl resin (Mitsui Chemical IncXLC-2L OH EW = 175 geq) Scheme 1 shows the chemicalstructure of the epoxy and the hardener

The TPP catalyst was obtained from Hooko Co TheTPP-BQ catalyst was synthesized by the authors and wasidentified using Fourier transform infrared spectroscopy(FTIR) and nuclear magnetic resonance (NMR) [20] Thechemical structure of the catalysts is described in Scheme 2

The filler was fused silica with a mean particle size(D50) of 20120583m (Tatsumori Co) The coupling agent was

glycidoxypropyltrimethoxysilane (Shin-Etsu Chemical Co)The release agent was ethylene glycol ester of montanic acid(Hoechst Co) The colorant was carbon black (Cabot CoCM 800)

The materials were weighed out in the ratios given inTable 1 and thoroughly kneaded using a two-roll mill withthe cold roller operated at 15∘C and the hot roller operated at120∘C After mixing EMC was cooled and pulverized Eachsample was then stored in a refrigerator at 4∘C

22 Instruments Calorimetric measurements were madeusing a differential scanning calorimeter (DSC) (Perkin-Elmer DSC-7) equipped with an intracooler Isothermaland dynamic-heating experiments were performed at a50mLmin nitrogen flow In dynamic curing the sample was


OO O CH

O

H2C CH2 CH2 CH2 CH2

CH3

CH3

CH3

CH3

(a)

(b)

OH OH OH

H2C H2C H2C H2C

119899


3

P

3

P+ sdot minusO O

(a)

(b)





119879)




119868(119905)Δ119867

119879





119903 =119889120572

119889119905= (1198961+ 1198962120572119898) (1 minus 120572)

119899 (1)


1and 119896



1and 119896


[22ndash24 26]

119896119894= 119860119894exp(minus119864119886119894

119877119879) (2)








ln(119889120572119889119905) = ln (119896

1+ 1198962120572119898) + 119899 ln (1 minus 120572) (3)


ln [ 119889120572119889119905(1 minus 120572)

119899minus 1198961] = ln 119896

2+ 119898 ln120572 (4)





ln(119889120572119889119905) minus ln (119896

1+ 1198962120572119898) = 119899 ln (1 minus 120572) (5)






1 100

40

80

120

160

Log(time) (min)

Rate

(minminus1)

TPP-BQ130∘C

150∘C165∘C

175∘C185∘C



0

50

100

150

200

250

1 10Log(time) (min)

TPP130∘C

150∘C165∘C

175∘C185∘C

Rate

(minminus1)







119868)






Δ119867119877

(J gminus1)Δ119867119879

(J gminus1) 120572I ()

130 170 12 182 934150 184 0 184 100

TPP-BQ 165 183 0 183 100175 185 0 185 100185 186 0 186 100130 171 13 184 929150 183 0 183 100

TPP 165 184 0 184 100175 183 0 183 100185 185 0 185 100







1and 119896

2


2 could be obtained






1198861and 119864

1198862values


1198861and 119864







1 Since 119896

1governs


120 140 160 180 2000

2

4

6

Temperature (∘C)

Tim

e of m

axim

um ra

te (m

in)

(a)

0

10

20

30

120 140 160 180 200Temperature (∘C)

Curin

g tim

e (m

in)

TPPTPP-BQ

(b)






Accelerator 119879 (∘C) 119898 1198991198961

(minminus1)1198962

(minminus1)1198641198861

(kJmolminus1)1198641198862


ln1198602

130 04 13 66 128150 04 14 65 617

TPP-BQ 165 05 10 202 1294 183 116 165 133175 06 10 398 2005185 13 11 1148 3308130 05 13 126 316150 05 13 165 1029

TPP 165 06 14 455 1893 126 96 129 123175 06 15 731 2910185 05 15 1109 4769

0005 0006 0007 0008

0

4

8

ln1198961

(minminus1)

1119879 (1K)

(a)

0005 0006 0007 00080

2

4

6

8

10

ln1198962

(minminus1)

1119879 (1K)

TPPTPP-BQ

(b)




119892)


119892value (120∘C)





0 10 20 300

20

40

60

80

100

Time (min)

Con

vers

ion

()

TPP-BQ

130∘C150∘C165∘C

175∘C185∘C


0 4 8 12 16 200

20

40

60

80

100

Time (min)

Con

vers

ion

()

TPP130∘C150∘C

165∘C

175∘C185∘C



0 20 40 60 80 1000

40

80

120

160

200

Conversion ()

Rate

(minminus1)

TPP-BQ130∘C150∘C165∘C

175∘C185∘C





0 20 40 60 80 1000

100

200

300

Conversion ()

Rate

(minminus1)

TPP130∘C150∘C165∘C

175∘C185∘C



4 Conclusions


(a)

(b)



Acknowledgments


References



































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials




OO O CH

O

H2C CH2 CH2 CH2 CH2

CH3

CH3

CH3

CH3

(a)

(b)

OH OH OH

H2C H2C H2C H2C

119899


3

P

3

P+ sdot minusO O

(a)

(b)





119879)




119868(119905)Δ119867

119879





119903 =119889120572

119889119905= (1198961+ 1198962120572119898) (1 minus 120572)

119899 (1)


1and 119896



1and 119896


[22ndash24 26]

119896119894= 119860119894exp(minus119864119886119894

119877119879) (2)








ln(119889120572119889119905) = ln (119896

1+ 1198962120572119898) + 119899 ln (1 minus 120572) (3)


ln [ 119889120572119889119905(1 minus 120572)

119899minus 1198961] = ln 119896

2+ 119898 ln120572 (4)





ln(119889120572119889119905) minus ln (119896

1+ 1198962120572119898) = 119899 ln (1 minus 120572) (5)






1 100

40

80

120

160

Log(time) (min)

Rate

(minminus1)

TPP-BQ130∘C

150∘C165∘C

175∘C185∘C



0

50

100

150

200

250

1 10Log(time) (min)

TPP130∘C

150∘C165∘C

175∘C185∘C

Rate

(minminus1)







119868)






Δ119867119877

(J gminus1)Δ119867119879

(J gminus1) 120572I ()

130 170 12 182 934150 184 0 184 100

TPP-BQ 165 183 0 183 100175 185 0 185 100185 186 0 186 100130 171 13 184 929150 183 0 183 100

TPP 165 184 0 184 100175 183 0 183 100185 185 0 185 100







1and 119896

2


2 could be obtained






1198861and 119864

1198862values


1198861and 119864







1 Since 119896

1governs


120 140 160 180 2000

2

4

6

Temperature (∘C)

Tim

e of m

axim

um ra

te (m

in)

(a)

0

10

20

30

120 140 160 180 200Temperature (∘C)

Curin

g tim

e (m

in)

TPPTPP-BQ

(b)






Accelerator 119879 (∘C) 119898 1198991198961

(minminus1)1198962

(minminus1)1198641198861

(kJmolminus1)1198641198862


ln1198602

130 04 13 66 128150 04 14 65 617

TPP-BQ 165 05 10 202 1294 183 116 165 133175 06 10 398 2005185 13 11 1148 3308130 05 13 126 316150 05 13 165 1029

TPP 165 06 14 455 1893 126 96 129 123175 06 15 731 2910185 05 15 1109 4769

0005 0006 0007 0008

0

4

8

ln1198961

(minminus1)

1119879 (1K)

(a)

0005 0006 0007 00080

2

4

6

8

10

ln1198962

(minminus1)

1119879 (1K)

TPPTPP-BQ

(b)




119892)


119892value (120∘C)





0 10 20 300

20

40

60

80

100

Time (min)

Con

vers

ion

()

TPP-BQ

130∘C150∘C165∘C

175∘C185∘C


0 4 8 12 16 200

20

40

60

80

100

Time (min)

Con

vers

ion

()

TPP130∘C150∘C

165∘C

175∘C185∘C



0 20 40 60 80 1000

40

80

120

160

200

Conversion ()

Rate

(minminus1)

TPP-BQ130∘C150∘C165∘C

175∘C185∘C





0 20 40 60 80 1000

100

200

300

Conversion ()

Rate

(minminus1)

TPP130∘C150∘C165∘C

175∘C185∘C



4 Conclusions


(a)

(b)



Acknowledgments


References



































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials




1 100

40

80

120

160

Log(time) (min)

Rate

(minminus1)

TPP-BQ130∘C

150∘C165∘C

175∘C185∘C



0

50

100

150

200

250

1 10Log(time) (min)

TPP130∘C

150∘C165∘C

175∘C185∘C

Rate

(minminus1)







119868)






Δ119867119877

(J gminus1)Δ119867119879

(J gminus1) 120572I ()

130 170 12 182 934150 184 0 184 100

TPP-BQ 165 183 0 183 100175 185 0 185 100185 186 0 186 100130 171 13 184 929150 183 0 183 100

TPP 165 184 0 184 100175 183 0 183 100185 185 0 185 100







1and 119896

2


2 could be obtained






1198861and 119864

1198862values


1198861and 119864







1 Since 119896

1governs


120 140 160 180 2000

2

4

6

Temperature (∘C)

Tim

e of m

axim

um ra

te (m

in)

(a)

0

10

20

30

120 140 160 180 200Temperature (∘C)

Curin

g tim

e (m

in)

TPPTPP-BQ

(b)






Accelerator 119879 (∘C) 119898 1198991198961

(minminus1)1198962

(minminus1)1198641198861

(kJmolminus1)1198641198862


ln1198602

130 04 13 66 128150 04 14 65 617

TPP-BQ 165 05 10 202 1294 183 116 165 133175 06 10 398 2005185 13 11 1148 3308130 05 13 126 316150 05 13 165 1029

TPP 165 06 14 455 1893 126 96 129 123175 06 15 731 2910185 05 15 1109 4769

0005 0006 0007 0008

0

4

8

ln1198961

(minminus1)

1119879 (1K)

(a)

0005 0006 0007 00080

2

4

6

8

10

ln1198962

(minminus1)

1119879 (1K)

TPPTPP-BQ

(b)




119892)


119892value (120∘C)





0 10 20 300

20

40

60

80

100

Time (min)

Con

vers

ion

()

TPP-BQ

130∘C150∘C165∘C

175∘C185∘C


0 4 8 12 16 200

20

40

60

80

100

Time (min)

Con

vers

ion

()

TPP130∘C150∘C

165∘C

175∘C185∘C



0 20 40 60 80 1000

40

80

120

160

200

Conversion ()

Rate

(minminus1)

TPP-BQ130∘C150∘C165∘C

175∘C185∘C





0 20 40 60 80 1000

100

200

300

Conversion ()

Rate

(minminus1)

TPP130∘C150∘C165∘C

175∘C185∘C



4 Conclusions


(a)

(b)



Acknowledgments


References



































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials






Δ119867119877

(J gminus1)Δ119867119879

(J gminus1) 120572I ()

130 170 12 182 934150 184 0 184 100

TPP-BQ 165 183 0 183 100175 185 0 185 100185 186 0 186 100130 171 13 184 929150 183 0 183 100

TPP 165 184 0 184 100175 183 0 183 100185 185 0 185 100







1and 119896

2


2 could be obtained






1198861and 119864

1198862values


1198861and 119864







1 Since 119896

1governs


120 140 160 180 2000

2

4

6

Temperature (∘C)

Tim

e of m

axim

um ra

te (m

in)

(a)

0

10

20

30

120 140 160 180 200Temperature (∘C)

Curin

g tim

e (m

in)

TPPTPP-BQ

(b)






Accelerator 119879 (∘C) 119898 1198991198961

(minminus1)1198962

(minminus1)1198641198861

(kJmolminus1)1198641198862


ln1198602

130 04 13 66 128150 04 14 65 617

TPP-BQ 165 05 10 202 1294 183 116 165 133175 06 10 398 2005185 13 11 1148 3308130 05 13 126 316150 05 13 165 1029

TPP 165 06 14 455 1893 126 96 129 123175 06 15 731 2910185 05 15 1109 4769

0005 0006 0007 0008

0

4

8

ln1198961

(minminus1)

1119879 (1K)

(a)

0005 0006 0007 00080

2

4

6

8

10

ln1198962

(minminus1)

1119879 (1K)

TPPTPP-BQ

(b)




119892)


119892value (120∘C)





0 10 20 300

20

40

60

80

100

Time (min)

Con

vers

ion

()

TPP-BQ

130∘C150∘C165∘C

175∘C185∘C


0 4 8 12 16 200

20

40

60

80

100

Time (min)

Con

vers

ion

()

TPP130∘C150∘C

165∘C

175∘C185∘C



0 20 40 60 80 1000

40

80

120

160

200

Conversion ()

Rate

(minminus1)

TPP-BQ130∘C150∘C165∘C

175∘C185∘C





0 20 40 60 80 1000

100

200

300

Conversion ()

Rate

(minminus1)

TPP130∘C150∘C165∘C

175∘C185∘C



4 Conclusions


(a)

(b)



Acknowledgments


References



































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials





Accelerator 119879 (∘C) 119898 1198991198961

(minminus1)1198962

(minminus1)1198641198861

(kJmolminus1)1198641198862


ln1198602

130 04 13 66 128150 04 14 65 617

TPP-BQ 165 05 10 202 1294 183 116 165 133175 06 10 398 2005185 13 11 1148 3308130 05 13 126 316150 05 13 165 1029

TPP 165 06 14 455 1893 126 96 129 123175 06 15 731 2910185 05 15 1109 4769

0005 0006 0007 0008

0

4

8

ln1198961

(minminus1)

1119879 (1K)

(a)

0005 0006 0007 00080

2

4

6

8

10

ln1198962

(minminus1)

1119879 (1K)

TPPTPP-BQ

(b)




119892)


119892value (120∘C)





0 10 20 300

20

40

60

80

100

Time (min)

Con

vers

ion

()

TPP-BQ

130∘C150∘C165∘C

175∘C185∘C


0 4 8 12 16 200

20

40

60

80

100

Time (min)

Con

vers

ion

()

TPP130∘C150∘C

165∘C

175∘C185∘C



0 20 40 60 80 1000

40

80

120

160

200

Conversion ()

Rate

(minminus1)

TPP-BQ130∘C150∘C165∘C

175∘C185∘C





0 20 40 60 80 1000

100

200

300

Conversion ()

Rate

(minminus1)

TPP130∘C150∘C165∘C

175∘C185∘C



4 Conclusions


(a)

(b)



Acknowledgments


References



































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials




0 10 20 300

20

40

60

80

100

Time (min)

Con

vers

ion

()

TPP-BQ

130∘C150∘C165∘C

175∘C185∘C


0 4 8 12 16 200

20

40

60

80

100

Time (min)

Con

vers

ion

()

TPP130∘C150∘C

165∘C

175∘C185∘C



0 20 40 60 80 1000

40

80

120

160

200

Conversion ()

Rate

(minminus1)

TPP-BQ130∘C150∘C165∘C

175∘C185∘C





0 20 40 60 80 1000

100

200

300

Conversion ()

Rate

(minminus1)

TPP130∘C150∘C165∘C

175∘C185∘C



4 Conclusions


(a)

(b)



Acknowledgments


References



































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials




0 20 40 60 80 1000

100

200

300

Conversion ()

Rate

(minminus1)

TPP130∘C150∘C165∘C

175∘C185∘C



4 Conclusions


(a)

(b)



Acknowledgments


References



































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials




































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials



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