Localization of High-performance Polyimide Materials Needs More Time - Interview with Yang Shiyong, Researcher of Institute of Chemistry, Chinese Academy of Sciences
Click:0    DateTime:Jan.26,2022

By Chang Xiaoyu

High-performance polyimide materials – with outstanding features in production and properties, and hailed as one of the most promising engineering plastics in the 21st century – have huge potential in the high-tech industry, no matter as structural materials or functional materials. What is the current research and development status in China? What are the difficulties in achieving product localization and industrialization? You can find the answers in the exclusive interview with Yang Shiyong, Researcher of Institute of Chemistry, Chinese Academy of Sciences.

Three application areas

CCN: What is the current research and development status of high-performance polyimide materials in China? What do you think of the technologies to localize the products?

Yang Shiyong: China has researched polyimide materials since the 1970s, and has laid a foundation in developing high temperature resistant polyimide resins, films, fibers and foams. However, China lags behind western industrial powers, the US and Japan for example, in industrialization and engineering applications, especially in high-tech areas like IC chip manufacturing and packaging, electro-optic display, etc.

Benefiting from the burgeoning high-tech industry, China’s demand for high-performance polyimide materials has skyrocketed in recent years. Hence the urgent need to improve the industrialization technology level of high-performance polyimide materials.

CCN: What are the main application fields of high-performance polyimide materials in the future?

Yang Shiyong: High-performance polyimide materials will be mainly used in: 

* Electronic industry, more specifically, in chip manufacturing and packaging, assembly of electronic components, etc.

* Flexible display industry – Due to the property to bend, polyimide films may replace glass to produce flexible photoelectric display screens and flexible photoelectric detectors. This is vital for intelligent robot and intelligent UAV industries.

* Military industry, e.g. areas of aerospace, aviation and space exploration.

Given excellent properties of high-performance polyimide materials, enterprises are trying to use them to replace traditional materials, leading to many new application areas.

Breakthroughs in four key technologies

CCN: What breakthroughs have you and your team made in high-performance polyimide materials related technologies?

Yang Shiyong: The Institute of Chemistry CAS started researching the materials in the 1970s. I started in 1996 when I returned to China, with main research topics including high temperature resistant polyimide resins, high-performance polyimide films, photosensitive polyimide resins, high temperature resistant polyimide foams, polyimide super engineering plastics, etc. Some breakthroughs have been made in:

* High-performance polyimide film industrialization technology – We helped Shenzhen RAYITEK Hi-Tech Film Co., Ltd. employ thermal imidization process to achieve industrialization of polyimide films, satisfying demand from electrical insulation and electronic circuit board areas. In addition, we worked together with Jiangsu Zhongtian Technology Group, realizing continuous production of electronic-grade polyimide films via adopting chemical imidization method. And products - same as or better than foreign counterparts – have been used in domestic FCCL production.

* High heat resistant lightweight structural foam industrialization technology – After 17 years of hard work, we invented production technology regarding polymethacrylimide (PMI) rigid closed-cell structural foams with resistance to 180℃, and constructed a 3 000 t/a PMI foam production line, resulting in localization and industrialization of PMI foams used in many important areas like aerospace.

* High temperature resistant polyimide resin production technology – Some new products were invented, such as high temperature resistant polyimide resin series products - with different heat resistance grades and suitable for different molding processes. Composite structural components made by the mentioned series products and carbon fibers (or quartz fibers) could be used in high temperature environment (300-450℃), meeting requirements from aviation area.

* Photosensitive polyimide (PSPI) production technology – We mastered key production technologies, and made breakthroughs in localization and industrialization of PSPI, which enjoys not only comprehensive excellent properties of polyimide but photoetching drawing function of photoresists. PSPI is core materials of integrated circuit (IC) manufacturing and packaging.

Suggestions on localization of new high-end chemical materials

CCN: How to promote cooperation among enterprises, universities and research institutes to speed up localization of new high-end chemical materials?

     Yang Shiyong: Scientists have R&D advantages, but to develop industrialized products, teaming up with enterprises is necessary. Hence, scientists are encouraged to set up own laboratories and R&D teams with the help of enterprises. For many high-tech projects, 10 to 15 years are probably needed to make breakthroughs. Therefore, enterprises are advised to give more time to scientists.