In 2015, China’s plastics industry output exceeded 2,100 billion, as Guangdong province again led the way in the country’s plastic manufacturing by contributing the largest share in this number.

However, handicapped by high energy consumption, excessive waste and technique limitations, the province’s plastics industries is not strong enough compared to the volume of its body, calling for improvements in technology innovation and industrial upgrading. 

Now a set of techniques developed by SCUT scientists have shown a new path for plastic enterprises to upgrade their manufacturing lines. The patented technology, “polymer material plasticizing and transporting method and apparatus based on draft flowing deformation”, was invented by a research team led by SCUT Professor Qu Jinping, a renowned scientist of mechanical engineering and advanced materials, and an Academician of the Chinese Academy of Engineering.

This technology means to preserve large molecules and long fibers during plastic processing, while creating a better way to uniformly blend materials of different viscosities. It works effectively to improve performances of plastics and composite materials.

Take polyvinyl chloride (PVC) as an example. It is known that the material is not easy to process, but in the meanwhile, PVC pipes are still widely used in urban infrastructures, industries and agriculture, which bring a huge market demand that requires more efficient processing techniques on the material.

In December 2016, based on the above mentioned technology, a new type of advanced equipment for plasticizing and transporting polymer materials was delivered for use to a plastic enterprise in Guangdong. In contrast to conventional apparatus, the length of this new equipment’s extrusion system is reduced by 50%, and its energy consumption is reduced by 30%. The efficiency of the production line is thus enhanced by 25%, while the tensile strength, impact strength and pressure resistance of the pipes all get significantly improved, marking a milestone in PVC processing techniques.

Another important application of the technology is to contain pollution caused by agricultural films, for instance, in cotton fields. After a long period of sunshine and natural weathering, films may age and degrade, leaving massive debris in the field. The first damage it can do is contaminating the quality of the soil, and then some of the plastic remains may get into the harvested cottons, dragging down cottons' grade and price, even sales volume.

Now this difficult situation changes with the processing method that enables factories to produce high performance agricultural films with materials made up of larger molecules. The durability of films is greatly prolonged, and it is feasible to recycle whole pieces of films after a growth cycle of the plant.

The scientific progress also provided a new possibility to plastic pipes made up of ultra-high molecular weight polyethylene (UHWMPE). These pipes can be quite useful for transporting materials and supplies, in particularly with regard to fields such as petrochemical engineering, mining engineering, and river and sea dredging.

Currently, steel pipes are frequently used on the above occasions but they are showing shortages of poor resistances to erosion and abrasion, which may result in a short life of the pipes, requiring replacements after only several months of use. That’s why people have been looking for another material that is more solid, more durable and lighter to replace steel, and UHWMPE answers to these needs as a perfect option.

Up till now, the research team led by Professor Qu Jinping has filed over 30 patent applications based on the invention. Its key technology has been granted patents in Japan, the US, Europe, Russia and Canada.

After winning the China Patent Golden Award in 2014 and the State Technological Invention Award in 2015, the patent also received prizes from the Hong Kong-based Ho Leung Ho Lee Foundation in 2016, recognizing the team’s significant participation in helping industrial upgrading of the province and the country.