高马来酸酐SMA及梳型表面活性剂SMA-g-MPEG的制备

Preparation of SMA and Comb-shaped Surfactant SMA-g-MPEG

分别采用均相聚合及非均相沉淀聚合法,制备了苯乙烯马来酸酐共聚物(SMA)。考察了引发剂种类和浓度、单体摩尔比、反应温度和反应时间等因素对SMA中马来酸酐(MA)摩尔分数的影响。优化的反应条件为:采用非均相聚合法,以过氧化二苯甲酰(BPO)为引发剂,聚合时间8 h,温度80℃,引发剂浓度0.01 mol/L,单体摩尔比n(St)∶n(MA)=1∶1.5,在该条件下,所合成SMA中马来酸酐的摩尔分数为37.43%,黏均相对分子质量约为89 000,交替性好。将得到的SMA与聚乙二醇单甲醚(MPEG)进行接枝反应,可以制得临界胶束质量浓度为1.03 g/L、表面张力为35.29 mN/m的梳型表面活性剂(SMA-g-MPEG)。

Due to its special structures, comb-shaped surfactants have the advantage in the use of dispersion stabilizer,interface modifier and biopharmacy application etc. Much attention has been paid to the preparation and application of comb-shaped surfactants. Poly （styrene-co-maleic anhydride ） （SMA） with high x （MA） has been prepared to get the comb-shaped surfactant by grafting poly （ethylene glycol）monomethyl ethers （MPEG） onto SMA. SMA was prepared by homogeneous and heterogeneous radical copolymerization. The effects of reaction conditions, such as initiator, initiator concentration, monomer molar ratio, temperature and time on x （MA） in SMA, were investigated. The result showed that the SMA with high x （ MA ） can be obtained by heterogeneous copolymerization process with benzoyl peroxide（BPO） as an initiator and the optimum reaction conditions were 8 h,80℃ ,0. 01 mol/L benzoyl peroxide （BPO） and 1：1.5 St to MA molar ratio. In preparing SMA, X （MA） was 37.43% and the viscosity-average molecular weight was about 89 000. The comb-shaped polymeric surfactant （SMA-g-MPEG） could be prepared by grafting MPEG onto SMA. The critical micelle concentration and surface tension of the SMA-g-MPEG were 1.03 g/L and 35.29 mN/m, respectively.