摘要
以无水乙醇为溶剂, N,N-亚甲基双丙烯酰胺(MBAA)为交联剂,在50℃下将丙烯酸十八酯(ODA)与甲基丙烯酸(MAA)进行共聚,合成了丙烯酸十八酯(ODA)与甲基丙烯酸(MAA)的共聚物凝胶; 研究了共聚组成对凝胶性能的影响。结果表明:经二甲亚砜(DMSO)平衡溶胀后的凝胶,在[ODA]:[MAA]摩尔比为1:3时,具有较高的规整性和较高的溶胀倍率。DSC测定表明在温度变化过程中聚合物凝胶存在有序-无序结构的转变。将共聚物凝胶在由不同极性的溶剂环己醇和DMSO组成的混合溶剂中溶胀,发现聚合物凝胶在极性溶剂DMSO中的规整性最高,随着小极性溶剂环己醇的比例加大,混合溶剂的极性下降,聚合物凝胶在混合溶剂中的规整性逐渐降低,相变温度向低温迁移,吸热和放热量降低,至环己醇含量≥40%后,在升温-降温过程中其吸放热量均为0,不发生相变,这说明溶剂的极性对聚合物凝胶的规整性有较大的影响。
Using absolute ethanol as solvent, N,N'-methylene-bis-acrylamide (MBAA) as cross-linking agent, cross-linked copolymer gels were successfully prepared by copolymerization of octadecyl acrylate (ODA) and methacrylic acid (MAA) at 50°C. The copolymerized gels showed transformation of the structure from order to disorder with the change of temperature detected by the characteristic of differential scanning calorimetry (DSC). The effects of composition of monomer on the properties of the gels were studied. It was found that the poly(ODA-co-MAA) gel with [ODA]:[MAA]=1:3 (molar ratio) exhibited higher ordered structure and higher degree of swelling in dimethylsulfoxide (DMSO). Using the mixture of cyclohexanol (dielectric constant=15 at 25°C) and DMSO (dielectric constant=48.9 at 20°C), the effect of polarity of solvent on the ordered structure of the gels was also investigated. It was found that a better regularity was obtained in DMSO, and the regularity, phase change temperature and the endothermic and exothermic amount were decreased with increasing of the amount of cyclohexanol; the endothermic and exothermic amount was 0, when the amount of cyclohexanol ≥40%(wt), indicating a significant effect of the polarity of solvent on the regularity of the gels.
出处
《高校化学工程学报》
EI
CAS
CSCD
北大核心
2004年第5期659-663,共5页
Journal of Chemical Engineering of Chinese Universities
基金
江苏省自然科学基金(BK2001141)。
关键词
凝胶
丙烯酸十八酯
规整度
甲基丙烯酸
Copolymerization
Crosslinking
Differential scanning calorimetry
Gels
Organic solvents
Polyacrylates
