接枝改性聚丁二烯胶乳胶乳的制备及其在水泥基复合材料中的应用

针对目前固井用胶乳抗盐能力和冻融稳定性差、增韧能力不足及综合性能欠佳的问题，以苯乙烯（St）为硬单体，聚丁二烯胶乳（PB）为种子软单体结合新型的功能单体，采用乳液接枝聚合方法合成了耐高温抗盐、冻融稳定性良好和增韧能力强的固井用胶乳HTL-100L。通过微观结构分析表明，各单体均参与了反应，分子结构高温下稳定，耐温能达到420℃左右。HTL-100L在硅酸盐水泥基复合材料中应用性能测试结果表明：HTL-100L显著提高了纯水泥的韧性，弹性模量降低近一倍，且其硅酸盐水泥石的强度发展良好。HTL-100L适用温度范围广（80~180℃），体系易调整和控制，综合性能良好，能够解决常规固井用胶乳存在的问题，改善油井水泥基复合材料的综合性能。

Preparation of graft-modified polybutadiene latex and its application in cement matrix composites

Currently, the use of latex for conventional cementing shows a series of problems such as low salt resistance, poor freeze-thaw stability, bad toughening ability and poor integrated performance. In view of the above-mentioned facts styrene(St) as hard monomer and polybutadiene latex (PB) as seed soft monomer combine new type of functional monomer, were used to synthesize the latex HTL-100L by emulsion grafting polymerization method, which had the properties of heat resistance, salt tolerance, good freeze-thaw resistance and strong toughening ability. Microstructural analysis suggests that all monmers are participated in the reaction and and the HTL-100L is the target product. The molecular structure is stable at high temperature about 420℃. The performance test of HTL-100L portland cement matrix composites shows that HTL-100L significantly improves the toughness of pure cement whose elastic modulus decreases nearly 100% and the strength of portland cement stone developes well. it has the advantages of wide applicable temperature range(80-180℃), easily controlled system and good integrated performance. Thus, it can be applied to solve the problems in latex for conventional cementing and improve the comprehensive performance of oil well cement matrix composites.