Poly(ethylene glycol)-polydimethylsiloxane (PEG-PDMS) crosslinked copolymers with mol ratios PEG:PDMS:Glycerol
of 5:3:2, 6:2:2 and 7:1:2 have been prepared and characterized. The synthesis of the copolymers was carried out
by the reaction between hydroxyl groups of PEG, PDMS and glycerol with isocyanate groups of 1,6-hexamethyelene
diisocyanate (HMDI). In the reaction, glycerol was acted as the cross linker. The copolymers were then characterized
by FTIR spectroscopy. The thermal behaviour was investigated by DSC and TGA. Based on FTIR results, the crosslinked
structure of the copolymers was confirmed by the presence of absorption peak at 3350 and 1710 cm-1 which indicated
the (-N-H) stretching and carbonyl (-C=O) correspond to urethane links. This showed that the hydroxyl groups of PEG,
PDMS and glycerol have reacted to isocyanate groups of HMDI. The copolymers showed melting temperature (Tm) of PEG
segments from 22°C to 27°C and glass transition temperature (Tg
) from -11°C to -6°C. Meanwhile, the PDMS segment
showed values from -53°C to -56°C for Tm, and Tg
from -118°C to -122°C. Data obtained from the thermal analysis
indicate that thermal stability increases with increasing PDMS mol ratio.