Chlorinated polypropylene (CPP) is widely encountered in day to day applications. It is used in such things as polyolefin coatings, agglutinants, printing ink and compatibility assistants as it has excellent abrasion resistance, age resistance and acid and alkali resistance. Understanding any breakdown of this material is therefore extremely important.
Studies of ultrasonic irradiation show that it can cause the degradation of polymers. The effects of variables like temperature, ultrasound intensity, solution vapour pressure, frequency of ultrasonic waves and polymer concentration have been investigated but until now chlorinated polypropylene has been largely ignored.
This work by Si-Ye Tang and Da-Zhuang Liu from Zhengzhou University, published in the open access materials journal AZoJomo, examines the ultrasonic degradation of CPP. The goal of the work is to accurately determine the kinetic equation of CPP in toluene solution under ultrasonic irradiation.
The researchers found that new relationships and equations were required to characterize the degradation of CPP. With this hurdle overcome they found that the ultrasonic degradation of chlorinated polypropylene decreased with increasing CPP concentration while the limiting molecular weights increased with increasing concentration.
They also found that the degree of ultrasonic degradation is more pronounced in the more dilute solutions.
The article is available to view at https://www.azom.com/Details.asp?ArticleID=3632