摘要
利用高效的点击反应,将小分子紫外光吸收剂接到聚氯乙烯(PVC)上,制得PVC基光稳定剂,可解决以往小分子光稳定剂与聚合物相容性差而导致的抗光老化性能持久性差和环境污染等问题.首先,通过叠氮基的亲核取代反应制得不同取代率的叠氮化PVC(PVC-N3),2,4-二羟基二苯甲酮的4位羟基炔丙基化得到含炔基的2,4-二羟基二苯甲酮(2,4-DHBP-P).接着,PVC-N3与2,4-DHBP-P通过铜催化的叠氮-炔基Husigen环加成反应制得紫外光吸收剂含量不同的PVC基紫外光吸收剂(2,4-DHBP-PVC).在2,4-DHBP-PVC的紫外光辐照试验中,2,4-DHBP-PVC表现出很好的抗光老化性能,其羰基亚甲基比最低至0.03998,远远小于PVC的羰基亚甲基比(0.3331).
Poly(vinyl chloride) (PVC)-based light stabilizer was prepared by introducing the lower molecular UV absorbents into PVC using quantitative click reaction, which could avoid some defects (low permanence of light aging resistance property and environmental pollution) caused by poor polymer compatability of low molecular UV absorbent. Azide groups were firstly introduced into the backbone of PVC via a nucleophilic reaction to obtain PVC-N3 with different substitutive rate, and 2,4-dihydroxy-benzophenone (2,4-DHBP) was treated with propargyl bromide to prepare alkynyl-containing 2-hydroxy-4- (prop-2-ynyloxy)benzophenone (2,4-DHBP-P). Then, copper-catalyzed Husigen-Click cycloaddition reaction was performed between the pendant azide groups of PVC-N3 and alkynyl of 2,4-DHBP-P to afford the desired PVC-based UV absorbents (2,4-DHBP-PVC) with different amounts of benzophenone moieties. These 2,4-DHBP-PVC showed great resistance to pho- tonging while exposed to UV irradiation. Their ratio of carbonyl to methylene group were far lower than that of pure PVC (0.3331) after UV irradiating for 200 h, and the minimum value is about 0.03998.
出处
《有机化学》
SCIE
CAS
CSCD
北大核心
2016年第8期1963-1969,共7页
Chinese Journal of Organic Chemistry
关键词
聚氯乙烯
紫外光吸收剂
光老化
poly(vinyl chloride)
UV absorbents
photoaging