端环氧基聚苯乙烯与ECH的接枝共聚及其产物的性能

CHARACTERIZATION AND PROPERTIES OF COPOLYMER OBTAINED FROM COPOLYMER IZATIONOF EPOXY ETHER TERMINATED POLYSTYRENE WITH EPICHLOROHYDRIN

以Al(i-Bu)_3:H_3PO_4:H_2O:二甲基苯胺=1:0.25:0.25:0.1—0.15(mol比)组成的体系为催化剂,研究了端环氧基聚苯乙烯(PSt-ep)大单体与环氧氯丙烷(ECH)的接枝共聚。结果表明,当PSt-ep/ECH=25％—56％(质量),PSt-ep的(?)_n为(4.24—6.07)×10~3时,ECH转化率大于95％,接枝效率为40％—85％。共聚物经IR,~1H-NMR、动态力学谱和电镜表征,表明是规整接枝共聚物。随PSt-ep大单体分子量的增大(2.63×10~3—8.04×10~3),拉伸强度增高(2.9—12.1MPa),扯断伸长率下降(300％—140％),永久变形下降(8％—4％),硬度有所增高(55—80度,邵尔A型)。共聚物可重复熔融加工。在PSt/PECH(3/7,质量比)共混物中加入2％(质量)共聚物,后者具有良好的增容作用。共聚物的耐油性和耐溶剂性优于PSt,与PECH相近。

The graft copolymerization of epoxy ether terminated polystyrene (PSt - ep) macromer with epichlorohydrin (ECH) was studied by using a quaternary catalyst system which was composed of Al (i-Bu)3, H3PO4, H2O and amine in the molar ratios of 1 : 0.25 : 0.25 : 0.1-0.5 .The results showed that when the mass ratio of PSt-ep/ECH = 25% -56% ,and Mn of PSt-ep was (4.24 - 6.07) × 103, the conversion ratio of ECH was greater than 95% , and the graft efficiency was 40% - 85% . The purified copolymer was characterized by IR ,1H-NMR ,DMS and TEM to be a copolymer with uniform grafts .When the molecular weight of PSt-ep macromer increased from 2.63 × 103 to 8.04×103, the tensile strength of graft copolymer increased from 2.9 MPa to 12.1 MPa , the elongation at break decreased from 300% to 140% , permanent set decreased from 8% to 4% , Shore hardness increased from 55 A to 80 A . The graft copolymer could be melted and processed repeatedly , and its oil and solvent resistances were better than PSt , and similar to PECH .