5.05 d_3 2nov07 loh yueh feng opsp iufro new

7/30/2019 5.05 D_3 2nov07 Loh Yueh Feng Opsp Iufro New

1/24

ENHANCING PROPERTIES OF OILPALM

STEM PLYWOOD THROUGH PRE-

TREATMENT OF PHENOLIC RESIN

Loh Yueh Feng

Institute of Tropical Forestry and Forest Product

Universiti Putra Malaysia

Serdang Selangor MALAYSIA


2/24

100,000 hectares + 13.6million OPS due toreplanting each year(Anon 2005)

Total 4.5 million m3

plywood can be produce

INTRODUCTION

Rapid growth of oil palm

Plantation in Malaysia.

1990 (1.7 MILLION ha)2006 (4.5 MILLION ha)


3/24

INTRODUCTION

Based on 13.6 MILLION stems, about 4.5million m3 of OPS plywood can be producedeach year.

Taking the selling price of OPS plywood atRM1,000/m3, this would generate a revenueof RM4.5 billion to the plywood industry.

If the QUALITY can improved, the price canbe doubled, the revenue from palm plywood

will reach RM 4.5 billion/year

Export market: United States, UnitedKingdom, and Japan Due to its environmentfriendliness, lightness, and easy to workwith.

International acceptance: Certified asGREEN PRODUCT if the use of non-woodmaterial > 10% - under sustainable forestresources


4/24

Contain two distinctly different materials:Contain two distinctly different materials:

solid vascular bundle and loosesolid vascular bundle and loose

parenchyma cellsparenchyma cells

Rough surfaceRough surface Less stable (shrink and swell more)Less stable (shrink and swell more)

1. Low Quality Veneer1. Low Quality Veneer

high adhesive consumption

Use as core veneers

COMMON PROBLEMS IN THE MANUFACTURE OF OIL

PALM STEM PLYWOOD


5/24


PALM STEM PLYWOOD

Low strength OPS plywoodLow strength OPS plywood

Low dimensional stabilityLow dimensional stability

Low-grade Palm Plywood

Categorised under Utility-Grade

Current market price USD260/m3

2. Low Price Palm Plywood2. Low Price Palm Plywood


6/24

Unevenly distributionof vascular bundlesalong the radialdirection of stem -variation of density

values at differentparts of the oil palmstem.

Wide range density ofoil palm veneers- affect theperformance ofPlywood


PALM STEM PLYWOOD

3. Variation of density3. Variation of density

high density

(600 kg/m3)

medium density

(400-600 kg/m3)

low-medium

density(


7/24

Enhancement of veneer quality through

resin treatment

To develop effective resin treatment to

improve the quality of OPS veneers

To determine suitable adhesive spread rate

for oil palm stem veneers To determine the mechanical properties of

pre-treated OPS plywood

OBJECTIVES


8/24

MaterialsOPS veneer : Outer layer (1st stage peeling, 358 - 442kg/m3)

Inner layer (2nd stage peeling, 272 - 446kg/m3)

Treatment resin : Low Molecular weight PhenolFormaldehyde

Binder : Urea Formaldehyde


9/24

METHODOLOGY

Phase 1: Oil Palm Trunk VeneerProduction

Phase 2: Pre-treatment of OPTveneer using PF resin.

Phase 3: Production of Plywood


10/24

Oil Palm Stem Plywood

Untreated

(Control)

Treated

with Lmw PF

200g/m2

UF

Spread rate

250g/m2

UF

Spread rate

100%

Outer

Type

100%

Inner

Type

100%

Outer

Type

100%

Inner

Type

250g/m2

UF

Spread rate

200g/m2

UF

Spread rate

100%

Outer

Type

100%

Inner

Type

100%

Outer

Type

100%

Inner

Type

Parameter Used In This Study


11/24

Phase 1: Veneer ProductionPhase 1: Veneer Production

Log cutting Peeling Clipping

Veneer stackingInner peelingDrying


12/24

Phase 2: Development of treatment method

1. OPS veneers were segregated into outer and inner type

2. Dry the veneer to 6-8% MC

3. Soaking of veneers in LmwPF by passing the veneersthrough a container full with LmwPF resin for ~5seconds

4. Pre-pressing (between 2 rollers) to squeeze out theexcessive resin. The pressure is set until screw tight.

MC of treated veneers should be between 20-30%5. Drying of phenolic treated veneers at 60C for 48 hours.

Final MC between 6-7%

The optimum procedure for treating OPS

veneers with LmwPF is as follows:


13/24

Phase 2: Treatment of VeneerPhase 2: Treatment of Veneer

UF and PF resin

Veneer treated with PF

Roller pressing machineVeneer after pressing

Treatment

Continue


14/24

Continue

Sticker


15/24

Phase 3: OPS Plywood ManufacturedPhase 3: OPS Plywood Manufactured

Glue spread Cold press

Hot pressOPS plywood


16/24

Properties Assessment

Mechanical Test

Static bending test BS EN 310 Bonding test BS EN 314-1


17/24

Average Density Increment of OPT Veneer and Plywood after

Treated with Lmw PF

146247092531539318.98Inner

197178575436756515.86Outer

Increase in

Plywood

Density

(%)UntreatedTreated

Increase

in

Veneer

Density

(%)

UntreatedTreated

Resin

Solid

Uptake

(%)

(Kg/m3)

Veneer Density OPT Plywood

(Kg/m3)


18/24

Percentage of MOR increment

Inner type gave highpercentage of incrementabout 119% for 200g/mglue spread rate.

The lowest incrementwas 250g/m glue spread

rate with 22%.

Shows that, treatmentdo help increase strengthproperties of OPS veneerand reduced the amountof resin consumption.

Mean of MOR For OPS Plywood

34.55

26.37

43.62

35.02

12.47

17.1

27.3

20.83

0

510

15

20

2530

35

40

4550

M

P

aOuter

Inner

Untreated Treated

200 200250 250


19/24

Percentage of MOE increment

The highest result for MOE

increment is outer type with

250g/m glue spread rate.

Treating the veneer withLmwPF resin had increasedthe stiffness by 67%

The lowest increment was

inner type with 200g/m glue

spread rate.

Shows that treatment helpto increase stiffness

properties of the boards.

Mean of MOE For OPS Plywood

4763

7722

5205

2031

3090 3179

1944 1903

0

10002000

3000

4000

5000

6000

7000

8000

9000

M

P

a Outer

Inner

Untreated Treated

200 200250 250


20/24

Glue Bond Shear Strength of Phenolic-treated OPS Plywoodin Dry Test and Wet Test (cold water)

1.047

0.622

0.711

0.605

0

0.2

0.4

0.6

0.8

1

1.2

S

h

ear

Stren

th

M

P

a

Outer Lay-up

Inner Lay-up

TreatedUntreated

Dry Test

0.534

0.378

1.683

0.939

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

S

hear

Stren

th

M

P

a

Outer Lay-up

Inner Lay-up

Untreated Treated

Wet Test


21/24

84

86

88

90

92

94

96

98

100

Untreated Treated

Outer

Inner

0

20

40

60

80

100

Untreated Treated

Outer

Inner

Percentage of Wood Failure of Phenolic-treated OPS

Plywood in Dry Test and Wet Test (cold water)

Dry Test

Wet Test


22/24

Strength Retention of Phenolic-Treated OPS Plywood

75.1062.48

160.74150.96

0.00

20.00

40.00

60.00

80.00

100.00

120.00

140.00

160.00

180.00

Outer Lay-up

Inner Lay-up

Untreated Treated

Further improvement of

bond quality

On going analysis is

currently conducted to

look at the cured

glueline whether some

crosslinking had

occurred betweenPhenolic-treated

veneer and UF resin.


23/24

Conclusions

Treatment of OPS veneer with LmwPF has significantlyimproved the strength.

Segregating the veneers by density (outer= 358 - 442kg/m3

inner= 272 - 446kg/m3 ) had increased the averagestrength of the OPS plywood.

Greater improvement was seen in the performance ofplywood made from the lower-density-inner veneers.

The technique used in this study was able to enhance thestrength and bond quality properties of plywood madefrom OPS veneer, as well as, reduced the amount of resin

consumption.


24/24

5.05 d_3 2nov07 loh yueh feng opsp iufro new

Documents