화학공학소재연구정보센터
Journal of Polymer Science Part A: Polymer Chemistry, Vol.37, No.10, 1393-1402, 1999
Synthesis and thermal properties of a novel lactose-containing poly(N-isopropylacrylamide-co-acrylamidolactamine) hydrogel
An improved, simple, and efficient method for the synthesis of lactose-containing monomer acrylamidolactamine (LAM) has been reported. Free radical copolymerization of this monomer with N-isopropylacrylamide (NIPAM) in the presence of the crosslinking reagent N,N'-methylenebisacrylamide (BisA) (1.2 mol %) proceeded smoothly in an aqueous solution using potassium persulfate (KPS) and N,N,N',N'-tetramethylethylenediamine (TMEDA) as the initiating system and gave transparent hydrogels. Reactivity ratios were estimated from copolymerization reactions carried out in solution without BisA crosslinker and at low conversion, by using both linearization and nonlinearization methods. They were found to be r(LAM) = 0.75 and r(NIPAM) = 1.22. The swelling behavior of the hydrogels was studied by immersion of the hydrogels in deionized water at different temperatures. Equilibrium water uptake was increased when the LAM content was higher than 47 mol %, and reached approximate to 44-fold with 100 mol % LAM at room temperature. Depending on the composition, the gels showed sharp swelling transitions with small changes in temperature. Differential scanning calorimetry (DSC) was used to characterize the swelling transition and the organization of water in the copolymer hydrogels. The amounts of freezable water in these hydrogels ranged from 81 to 89%, and was not correlated to the content of the sugar monomer. These gels have potential applications as biocompatible materials.