材料期刊网

以异佛尔酮二异氰酸酯(IPDI)和二乙醇胺(DEOA)为原料,经一步法自缩聚反应制备超支化聚氨酯(HPU-OH).再以聚乙二醇(PEG200)、IPDI和丙烯酸羟乙酯(HEA)为原料合成一端为异氰酸基团、另一端为双键的预聚体IPDI/PEG200/HEA,将其接枝到HPU-OH后合成含柔性链超支化聚氨酯丙烯酸酯(HPUA).优化了合成条件;并采用FT-IR、1H NMR和GPC对其结构和组成进行了表征.以1-羟基环己基苯基甲酮(Irgacure 184)作为光引发剂,对HPUA涂膜紫外光固化后进行测试.结果表明:优化后IPDI/PEG200/HEA的合成条件为温度35℃、催化剂二月桂酸二丁基锡(DBT-DL)用量为丙烯酸羟乙酯质量的0.037 5％、反应时间为120 min;优化后HPUA的合成条件为温度70℃、DBTDL用量为0.05％、反应时间为120 min.合成的HPUA产品数均相对分子质量(Mn)为13 683,相对分子质量分布指数(PDI)为2.1;与同类产品相比,其固化速度快且涂膜柔韧性优异,光固化速度为3 s,柔韧性1 mm,铅笔硬度2H,附着力1级.

A hyperbranched polyurethane HPU-OH) was successfully synthesized from isophorone diisocyanate (IPDI) and diethanolamine (DEOA) via self-condensation.Meanwhile,a prepolymer IPDI/PEG200/HEA having isocyanate and double bond was synthesized from polyethylene glycol (PEG200),IPDI and 2-hydroxyethyl acrylate (HEA).Then a hyperbranched polyurethane acrylate (HPUA) with flexible chains was synthesized by graft reaction of the prepared prepolymer and HPU-OH.The synthesis conditions were optimized.The structure and composition of HPUA were characterized by FT-IR,1H NMR and GPC.Using 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure184) as a photoinitiator,the cured film of the UV-curable HPUA was tested.The optimal synthesis conditions of IPDI/PEG200/HEA was that the composition was reacted at 35 ℃ for 120 min at the presence of DBTDL as a catalyst with its dosage 0.037 5％ of the weight of HEA.And the optimal synthesis conditions of HPUA was that the composition was reacted at 70 ℃ for 120 min at the presence of DBTDL with its dosage 0.05 ％.The number average molecular weight was 13 683 and PDI was 2.1 as observed by GPC.Compared with the commercialized product of its kind,the UV-cured HPUA film displayed excellent properties such as fast UV-curing speed 3 s,flexibility 1 mm,pencil hardness 2H and adhesion 1 level.