"We succeeded in polypropylene contains no plasticizer in the course of processing and application, organic tin and low odor such as the goal, the development of the three are special polyethylene polypropylene material is only three domestic market contains no plasticizer and organic tin of high flow, high modulus, high crystallization homopolymerization polypropylene products, not only through the RoHS related inspection certification, plasticizer, organic tin also through many countries and regions in environmental health certification, fill the blank of domestic production."April 7, sinopec luoyang petrochemical company chemical process expert cao yuxin told reporters.
Cao yuxin said that with the help and guidance of Beijing institute of chemical industry and other institutions, luoyang petrochemical company has completed the development, promotion and industrial amplification of polypropylene special resins such as pph-y35x, pph-mn60, pph-mn90b and pph-mn15 in just over three years.Among them, the dedicated polypropylene resin pph-y35x fills the gap in the application field of high-end nonwovens in China.Pph-mn60, pph-mn90b and pph-mn15 products have become the only three products in the domestic market that do not contain plasticizer and organo-tin with high flow, ultra-high modulus and high crystallization.
It is understood that with the progress of science and technology, in recent years on the technical content of polypropylene special material demand is also more and more exuberant, product upgrading speed."Due to a variety of reasons, some polypropylene products contain plasticizer, organotin and strong smell, which have affected their market competitiveness."Cao yuxin said.
In view of this situation, the expert team of cao yuxin started to solve these problems in the processing and application of polypropylene in 2017.They found in the study of similar foreign products that in order to develop polypropylene products with no plasticizer and organotin, low odor, high rigidity, high hardness, high heat resistance, high gloss and other processing and application characteristics, we must solve a series of problems such as catalyst selection, modified base material.
In the process of developing new polypropylene products, in order to select the right main catalyst, the team extruded and granulated different types of catalysts and homogeneous polypropylene powder in the same process device.After repeated comparison, they found that the comprehensive properties of pph-mn60, pph-mn90b and pph-mn15 obtained by HR catalyst polymerization were obviously excellent, with low safety risks and free from substances prohibited by the eu such as plasticizers.
At the same time, in order to solve the problem of key process control points, the team optimized the process control points through repeated polypropylene product tests, improved the heat resistance temperature, transparency, glossiness of new polypropylene products, shortened the molding cycle of downstream products, and effectively solved the problem of polypropylene stiffness and balance.
"Another technical challenge we face is the performance of environmentally friendly polypropylene."Cao said that he led the team to conduct comparative analysis and pilot study on melting flow rate, relative molecular mass and its distribution, bending modulus, TVOC and other parameters."After tackling the problem, the TVOC content of polypropylene is greatly reduced, thus reducing the smell of polypropylene in the downstream processing and application process.