The COVID-19 pandemic made ECMO (Extracorporeal Membrane Oxygenation) a well-known life-saving medical device and demonstrated its irreplaceable value for patients with severe lung diseases. The membrane oxygenator, a core component of ECMO, relies on poly(4-methyl-1-pentene) (PMP) resin as its critical membrane material. Recently, the joint R&D team of Sinopec Ningbo New Materials Research Institute and Sinopec Zhenhai Refining has made a major technological breakthrough in the preparation of 4-methyl-1-pentene, the key raw material for PMP resin.
As the Spring Festival approached, researchers at Sinopec Ningbo New Materials Research Institute maintained tight progress on the project. One month prior, the propylene dimerization pilot unit at Zhenhai Refining successfully produced qualified 4-methyl-1-pentene for the first time, with an average purity exceeding 98%. This achievement marks a critical domestic breakthrough in the manufacturing of core materials for ECMO artificial lungs.
This milestone came after nearly ten years of continuous research and tackling technical bottlenecks by Zhenhai Refining’s propylene dimerization R&D team. Chen Ping, a researcher on the project, explained that 4-methyl-1-pentene is the essential monomer for synthesizing PMP resin, the indispensable raw material for producing the so-called "life membrane" used in ECMO membrane oxygenators.
For a long time, foreign enterprises have monopolized the entire PMP industrial chain. Before this breakthrough, the localization rate of 4-methyl-1-pentene stood at zero, meaning this vital medical raw material was fully dependent on imports.
To deliver domestically manufactured materials for ECMO life membranes, the R&D team carried out thousands of repeated experiments, parameter adjustments and data analyses, and finally achieved stable production of high-purity 4-methyl-1-pentene at the start of this year.
According to Chen Ping, high-performance catalyst is the core to obtaining high-purity 4-methyl-1-pentene monomers. There are 17 potential combination modes when two propylene molecules react, and the customized catalyst precisely guides the reaction to follow the only target synthesis path to generate the required monomer.
This breakthrough of a long-term stuck foreign monopoly technology is a typical example of Sinopec Zhenhai Refining’s transformation toward high-end new material manufacturing. Following the commissioning of high-end synthetic new material projects in Phase II of Zhenhai Petrochemical Base, the research institute has independently developed 56 medium and high-end polyolefin products, among which multiple grades fill domestic market gaps.
The technical research work is still ongoing. Ling Yu, a R&D engineer of the team, stated that the current core research directions include boosting catalyst stability and raising product yield to pave the way for large-scale industrial production. "Reaching the purity standard is only the first step. Every one percentage point increase in yield will greatly cut the overall cost of industrial manufacturing," Ling Yu explained.
Another key research target shared by engineer Dong Ke is comprehensive utilization of by-products. After stable production of the main 4-methyl-1-pentene product, the team will explore ways to convert all by-products into high value-added chemical products to maximize resource utilization efficiency.
