The important derivative in this
category has the following structures.
The performance of sulphur-free tin stabilizers is good in all types
of emulsion and bulk PVC. used in suitable formulations, these give
rigid PVC high transparency and more importantly, very good weathering
stability. There are known difficulties in the use of alkyltin maleates
for rigid PVC processing. The PVC mass tends to adhere to hot parts
of the machinery. However, this can be completely prevented by addition
of a suitable lubricant or use of a blend of organotin carboxylate
with a small amount of special organotin mercaptide.