Stabilizer compositions useful for protecting clear polyvinyl chloride and other clear halogen-containing polymer compositions used in the manufacture of exterior weatherable products against discoloration and degradation caused by exposure to ultraviolet light and weathering in addition to heat comprising a latent mercaptan which degrades during processing of the composition at an elevated temperature to liberate a free mercaptan, in combination with a synergistic amount of a free phenyl salicylate compound. The latent mercaptan may be the sole heat stabilizer additive in the stabilizer composition, but the free mercaptan released during processing may also synergize the activity of organic-based or metal-based heat stabilizers such as metal salts and organometallic stabilizers such as organotin carboxylates and organotin mercaptides in the polymer composition.
Clear polyvinyl chloride and other clear halogen-containing polymer compositions containing these compounds are also provided which exhibit improved ultraviolet light stability and weatherability without detracting from their thermal performance.
用于保护透明聚
氯乙烯和其他透明含卤聚合物组合物的稳定剂组合物,这些组合物可用于制造室外耐候产品,防止因暴露于紫外线和风化以及热量而引起的褪色和降解,该组合物包括一种潜
硫醇,在组合物加工过程中,该潜
硫醇在高温下降解,释放出游离
硫醇,并与一定量的游离
水杨酸苯化合物协同作用。潜
硫醇可以是稳定剂组合物中唯一的热稳定剂添加剂,但在加工过程中释放的游离
硫醇也可以协同聚合物组合物中的有机基或
金属基热稳定剂(如
金属盐和有机
金属稳定剂(如
有机锡羧酸盐和
有机锡硫醇盐))的活性。
此外,还提供了含有这些化合物的透明聚
氯乙烯和其他透明含卤聚合物组合物,它们具有更好的紫外线稳定性和耐候性,而不会影响其热学性能。