低挥发不饱和聚酯涂料的固化

Curing of Low Volatile Unsaturated Polyester Coatings

为了降低不饱和聚酯固化过程挥发性和毒性,用衣康酸二甲酯代替苯乙烯作为不饱和聚酯固化活性稀释剂。探究了该体系引发剂、促进剂、稀释剂的用量及促进剂的选择,考察了实干时间、凝胶率、转化率、挥发分的变化,对比了衣康酸二甲酯和苯乙烯两种稀释剂对涂膜性能的影响。结果表明:衣康酸二甲酯为活性稀释剂时,该体系引发剂过氧化环己酮含量2.5%,促进剂异辛酸钴含量为引发剂质量的16%,稀释剂用量为30%,此时固化时间为5.5 h,凝胶率达到76%;固化前20 min略有挥发,40 min后基本没有挥发,固化挥发分为15%,较苯乙烯相比降低5%;固化完全时,转化率达到50%,而凝胶率达到76%。通过分析两种稀释剂作用下的涂膜性能可知,衣康酸二甲酯与苯乙烯一样能优化涂膜性能,但存在亲水性差,用量较多的缺点。

In order to reduce the volatility and toxicity of unsaturated polyester during curing process,dimethyl itaconate was used instead of styrene as the curing active diluent of unsaturated polyester.The dosage of initiator,accelerator,diluent and the choice of accelerant were investigated.The changes of dry time,gel rate,conversion rate and volatile matter were also investigated.The effects of two diluents of dimethyl itaconate and styrene on the properties of the coating were compared.The results showed that when the dimethyl itaconate was used as active diluent,the initiator peroxide content of cyclohexanone was 2.5%,the content of cobalt isooctanate is 16%of the initiator quality,the amount of diluent was 30%,the curing time was 5.5 h,the gel rate reached 76%.After 20 min curing,it slightly volatilized,and 40min basically did not volatilize.The volatilization rate is 15%,and 5%lower than that of styrene;when cured,the conversion rate reaches 50%,and the gel rate reaches 76%.According to the analysis of the coating properties under the action of two diluents,dimethyl itaconate,like styrene,can optimize the coating properties,but it has the disadvantages of poor hydrophilicity and high dosage.