powerpoint presentation (polymer blend)

7/24/2019 PowerPoint Presentation (polymer blend)

1/14

POLYMERS BLENDS


2/14

Similar to the other rawmaterials , e.g. metals it isprincipally possible to ary

the properties o!macromolec"lar

s"bstances by mi#ing twoor more $i%erent polymers

.


3/14

OB&E'()*ES

1) To provide some design guidelines forthe

development of polymer blends

2 )To illustrate the commercialsignicance of

polymer blends


4/14

Polymer blen$s

miscibl

eimmiscible

+omogeno"s

to themolec"larleel,

)no phase

Phaseseparatio

n


5/14

Miscibility $epen$s on

- hy$rophobic

/ hy$rophilic0 Electronegatiity

1 polarity


6/14

Polymers DON2( M)3 .

In general, polymers are immiscible unlessthere are strongly favorable enthalpic

interactions

'on$itions !or polymer4polymer miscibility

0


7/14

Ma5ing Polymers Mi#(his presents a challenge to wo"l$4be

polymer blen$ers , (o ma5e thathappen, we hae to go bac5 to

the 7rstlaw o! thermo$ynamics . (hislaw says that when things change, they

change !rom a state o! more energy to astate o! less energy. (hin5 o! it this

way i! yo"8$ li5e a physics e#ample, aroc5 on top o! a mo"ntain will roll $own

to the bottom o! the mo"ntain moreeasily than a roc5 on the bottom will roll

to the top


8/14

9hat 7rst law o!thermo$ynamics hae to $o

with blen$ing polymers:in or$er to ma5e two polymers

mi#, we hae to ma5e themhae less energy when mi#e$than they wo"l$ be separate.

Let me "se an e#ample toill"strate. (wo polymers that

$o act"ally mi# polystyrene;poly


9/14

As you can see, both of these polymers havearomatic rings. As you may no!, aromatic rings lie

to stac up lie little he"agonal poer chips. #or thisreason, these t!o polymers lie to associate !itheach other. $o they blend very nicely.


10/14

Ma5ing Yo"r Own Blen$s

Blen$s are "s"ally ma$e in two ways

.(he 7rst way is to $issole two polymers in the samesolent, an$ then wait !or the solent to eaporate.9hen the solent has all gone away, yo"8ll be le!t witha blen$ at the bottom o! yo"r bea5er, pres"ming yo"rtwo polymers are miscible .9hile this metho$ wor5s7ne in the laboratory, it co"l$ get e#pensie i! yo"trie$ to $o this in$"strially..

So !or ma5ing blen$s in large amo"nts, yo" heat thetwo polymers together "ntil yo"8re aboe the

glass transition temperatureso! both polymers. =t this

point they will be nice an$ gooey, an$ yo" can mi#them together li5e a ca5e mi#.

(his is o!ten $one in machines s"ch as e#tr"$ers.9hen yo"r material cools, yo"8ll hae a nice blen$,

again, pres"ming yo"r two polymers are miscible.
http://pslc.ws/macrog/tg.htmhttp://pslc.ws/macrog/tg.htm


11/14

the composition range oer which thetwo polymers phase4separate isn8t

constant. )t can change withtemperat"re. >or some polymer pairs

that range gets smaller astemperat"re increases. Eent"ally, i!

yo" heat s"ch a pair high eno"gh,that range o! immiscibility will

become so small that it will

$isappear. (he temperat"re at whichthis happens is calle$ the "ppercritical sol"tion temperat"reor ?'S(.

(he graph on the right shows this.(he "psi$e4$own parabola is the

bo"n$ary between thosetemperat"res an$ compositions at

which there is one phase, an$ thoseat which there is phase separation.


12/14

(han5yo"


13/14

RE>EREN'ES-. )@=9=, (.A =BE, @.A +OND=, @.A =ND(S?'+)D=, E.A&. POLYM. S')., POLYM. '+EM.ED., -C, -0, -./. ()NF, E. P.A PE=R'E, E.M. =ND @9E), (. @.,&. POLYM. S'). POLYM.LE((. ED., -G, -G, /-.0. PE=R'E, E. M.A @9E), (. @. =ND M)N, B. Y.,&.

M='ROMOL. S'). '+EM., -G1, /-, --G-.1. 'OLEM=N, M. M., FR=>, &. >. =ND P=)N(ER, P.E( =L., SPE')>)' )N(ER='()ONS =ND (+EM)S')B)L)(Y O> POLYMER BLENDS, (E'+NOM)',

--, P./.


14/14

%roup names &

1. 'ohammad al(aarmeh

2. 'ohammad al(atiyat

*. 'ohammad halil

+. 'ohanad al(haala

-. 'ai abudayeh

. 'aram abuaamiah

powerpoint presentation (polymer blend)

Documents