Abstract :
Poly(ethylene glycol) methylether acrylate
(PEGMEA) and tetraethylene glycol diacrylate (TEGDA)
were first synthesized. The thermosensitive hydrogels
were then prepared from N-isopropylacrylamide
(NIPAAm), PEGMEA, and three crosslinkers with
different structures such as N, N¢-methylene-bis-acrylamide
(NMBA), TEGDA, and poly(ethylene glycol)
dimethacrylate (EGDMA). The influence of polymerization
factors such as the kind and amount of crosslinker
and initial total monomer concentration on the
swelling behavior, gel strength, effective crosslinking
densities, and number-average molecular weight between
crosslink points (Mc) for the present copolymeric
hydrogels was investigated. The results indicate that the
swelling ratios for the present copolymeric gels decrease
with increase in temperature. In addition, the results
also showed that the higher swelling ratios for the
present gels prepared from TEGDA were obtained due
to the larger space between the gel networks. The
crosslinking density depends on the swelling ratio and
the kind and extent of crosslinker. In addition, the drug
release behavior for the present copolymeric gels was
investigated.
