SMC制品耐老化性能的试验研究

STUDY ON AGEING RESISTANCE OF SMC PRODUCTS

试验采用UV-234作为SMC的紫外光吸收剂,考察了UV-234加入量对SMC固化性能和耐老化性能的影响,同时考察了模压时间和储存条件对制品耐老化性能的影响,并进行了自然气候老化、紫外光加速老化和热水老化试验。结果表明,UV-234能够提高SMC的耐老化性能,而且随着加入量的不断增大,耐老化性能先变好后变差,加入量为0.5份时效果最佳;模压时间对制品耐老化性能有一定程度影响,模压时间为4min时,效果略优于2min及6min;在室外自然气候条件下,SMC样板发生明显的黄变老化现象,而在密封储存条件下,未出现黄变老化的迹象,效果良好;紫外光加速老化试验表明,紫外光对制品的耐老化性能有较大程度影响;热水老化使SMC样板的力学性能有所降低,但保持率在80%以上。

In this paper using UV-234 as UV light absorbent of SMC,the effects of UV-234 content on curing process and ageing resistance of SMC sample plates were investigated,the effects of moulding time and storage condition on ageing resistance were also researched through natural exposing test,UV accelerated ageing and hot water ageing.The test results show that ageing resistance has been improved by adding UV-234,which has been enhanced at start and deteriorated in the end as the increasing of UV-234 content,the achievement is the best when content is 0.5phr.Moulding time has an unimportant effect on ageing resistance in a degree,it has better effctiveness than 2min and 6min when moulding time is 4min.A obvious xanthochromia ageing has occurred in natural exposing test outdoor,while it has no trend of xanthochromia ageing in sealed test with PP transparency film.UV has a dramatic effect on ageing resistance by UV accelerated ageing test.Hot water ageing decreases the mechanical properties of SMC sample plates but its conservation rate is above 80%.