The development of a novel polypropylene nucleating agent.

摘要

One of the biggest markets for polypropylene (PP) is the packaging industry. A main competitor in this market is polyethylene terephthalate (PET). One of PET'S biggest advantages over PP is clarity. There are several polypropylene clarifiers and nucleators on the market today; however they are usually high priced additives or have other disadvantages, depending on the application. This project began with the hopes of developing some novel cost effective clarifiers for polypropylene. Nyacol Nano Technologies, Inc., where I am currently employed, had developed a 50 nm spray dried colloidal silica product that was dispersible in solvents such as toluene, as well as in polypropylene. The problem was that, other than giving an excellent dispersion in polypropylene, the product did not enhance the physical or mechanical properties of the material in any way. By developing additional surface treatments for the 50nm colloidal silica, physical and mechanical property enhancements were now possible. Treatments have shown the ability of silica to act as a nucleating/clarifying agent in various grades of polypropylene by significantly increasing the crystallization temperature of the polymers at different loadings. Further research has led to treatments that show dramatic increases in Izod impact resistance and flexural modulus of different grades of polypropylene.