Bio-degradation of polyurethane based on bio-epoxy
This research is focused on the resistance to thermal, photo and bio-degradation of polymer thin films fiom renewable resources based on virgin and waste vegetable cooking oil from lndustri Kecil Sederhana (IKS's). Vegetable and waste vegetable oil polymers were grouped as virgin oil polymer (V...
Saved in:
| Main Authors: | , , , , |
|---|---|
| Format: | Thesis |
| Published: |
2012
|
| Subjects: | |
| Online Access: | http://eprints.uthm.edu.my/6875/ http://eprints.uthm.edu.my/6875/1/FRGS_0556.pdf |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | This research is focused on the resistance to thermal, photo and bio-degradation of polymer
thin films fiom renewable resources based on virgin and waste vegetable cooking oil from
lndustri Kecil Sederhana (IKS's). Vegetable and waste vegetable oil polymers were grouped
as virgin oil polymer (VOP) and waste oil polymer (WOP) thin films were prepared by
adding bio-monomer (lgm; 0.5 gm equivalent weight with polyol) with an appropriate
amount of 4, 4'-methylen-bis-(phenylisocyanate) (MDI) which thickness was 1 10-200pm
*O.OI pm. VOP and WOP thin films were tested for its resistance to thermal, photo and biodegradation
exposure for an extended period of time. The techniques utilized were
principally infra-red (R). The degradation of which upon thermal exposure was tested by
measuring the change in the carbonyl index, CI for WOP and VOP thin films. Thermal
exposure was measured at 50°C, 100°C, 150°C and 200°C up to 600 minutes. As the
temperature and the exposure time increased, the CI also increases for both WOP and VOP
at given temperature and 600 minutes from initial value of WOP is 0.296 to 0.391, 0.380,
0.413 and 0.427, meanwhile the initial value for VOP is 0.417 to 0.507,0.45, 0.433 and 0.44
respectively. The increased in CI formation for polymer after thermal exposure is
proportional to the number of chain scissions that occur in the polymer thin films associated
with the scission of the (-NHCO-O-), The absorption band of carbonyl groups near 1738 cmwas
broadened on increasing the heating time; also shoulders appeared on the main peaks
in a range at 1805-1800 cm*', The shape of the peaks for all spectra thin films are fairly
broad suggesting that more than one functional groups are formed within the carbonyl group
(C=O) family such as aldehydes, ketones, acids, esters, amides and anhydrides in the range
of 1805-1 704 crn-'. The TGA curves of the WOP and VOP display three distinct regions of
weight loss. The size of the peak at higher temperature was found to be correlated with the
amount of soft segment that c. a. n be attributed to the alkyl chain. It was established previously
that the amount of weight loss at the lower temperature is well correlated with the amount of
hard segment, suggesting that the degradation process starts in the hard segment based on the
MDI component. Biodegradability of polymer thin films was measured using soil burial test
according to EN IS0 846:1997. The percentage weight loss of VOP thin film in compost soil
burial test was significantly greater than those in peat soil burial test. IR-changes, yellowing
of tensile WOP thin films as a result of photo-degradation upon equatorial weathering were
studied. As a conclusion, mechanical properties of polymer thin films for WOP md VOP can
be strongly influenced by photo-oxidation upon equatorial weathering exposure. The
ductility disappears and the strength and strain at rupture strongly decrease at over 35%. The
active participant of OH group with isocyanate was lead to the creation of more stress point,
thus, lower energy needed for WOP thin films to bring to failure. Moreover, the occurrence
of surface damage enhances the degradation of these mechanical parameters. |
|---|