When rubber becomes liquid?

Is there liquid rubber? In addition to making car tires, it can also be used for 5G communications? Not long ago, Maoming Petrochemical's 5,000 tons/year high-performance liquid rubber unit successfully produced qualified products - liquid rubber for high-frequency copper clad laminates, and successfully delivered it to a leading domestic copper clad laminate industry company, opening the first order, marking that Sinopec's first batch of domestically produced high-performance liquid rubber has been successfully applied to the 5G communication field, which will provide key raw material support for my country's information industry security. What are the characteristics of liquid rubber? How does it play a role in the communication field? This edition reveals it for you.

What is liquid rubber?

Liquid rubber usually refers to a viscous polymer with a molecular weight of less than 20,000 and a certain fluidity at room temperature, which is easy to process and shape. Among them, conjugated diene liquid rubber is an important branch of liquid rubber. According to the different monomer compositions, it can be divided into liquid polybutadiene rubber, liquid polyisoprene rubber, liquid styrene-butadiene rubber and liquid butadiene-pentene rubber.

What is the difference between liquid rubber and solid rubber?

The biggest difference between liquid rubber and solid rubber is that it has a small molecular weight. It is liquid at room temperature. It is converted into solid after molecular chain cross-linking is induced by heating, light and other treatments, and has a pure texture.

What are the application fields of high-performance liquid rubber?

High-performance liquid rubber is the preferred material for one of the main substrates of high-frequency copper clad laminates. High-frequency copper clad laminates prepared with high-performance liquid rubber have fast signal propagation speed and no distortion during the transmission process. They are mainly used in 5G high-frequency communications such as mobile phones, computers, automobiles, military industry, and aerospace, flexible printing with high environmental protection requirements such as infant, food, and cosmetic packaging, as well as high-performance TPV (thermoplastic vulcanized rubber) and green tires.

How does high-performance liquid rubber play a role in copper clad laminates?

High-frequency and high-speed copper clad laminates are key components in the electronics industry. They are made by impregnating electronic glass fiber cloth or other reinforcing materials with resin adhesives, drying, cutting, and stacking them into blanks, and covering one or both sides with copper foil and hot pressing. They are mainly used to make circuit boards (PCBs). The performance of its main substrate, special resin, is directly related to the final performance of copper clad laminates. Liquid rubber has low dielectric constant and dielectric loss, is easy to heat-cured and molded, and has good heat resistance and mechanical properties after curing. It is the most ideal matrix resin for high-frequency and high-speed copper-clad laminates for 5G communications.

Development history of liquid rubber technology for 5G copper-clad laminates

●August 2018

The Beijing Institute of Chemical Industry received technical requirements from leading domestic copper-clad laminate companies, and the Yanshan Branch began to develop liquid polybutadiene rubber technology; in October, the Beijing Institute of Chemical Industry achieved a breakthrough in small-scale technical development and established a liquid rubber collaborative research team with leading domestic copper-clad laminate companies.

●May 2019

The first batch of liquid polybutadiene rubber produced by Sinopec passed the performance evaluation of leading domestic copper-clad laminate companies.

●January 2020

The Beijing Institute of Chemical Industry and leading domestic copper-clad laminate companies launched a joint research project on "R&D and application research of high-frequency electronic circuit substrates". In August, the Maoming Petrochemical SBS unit conducted a polymerization scale-up test of liquid polybutadiene rubber and prepared liquid polybutadiene rubber glue with excellent performance.

●October 2021

5,000 tons/year high-performance liquid rubber industrial production technology licensed to Maoming Petrochemical. In December, the "High-performance liquid rubber complete industrial technology development" project was included in Sinopec's "Ten Dragons" research project.

●August 2022

A key breakthrough was made in liquid rubber post-processing technology, achieving a metal impurity content of less than 10ppm (1ppm is one part per million) in the product.

●July 2023

5,000 tons/year liquid rubber industrial device completed and handed over. In October, qualified HB40 liquid butadiene rubber products for 5G copper clad laminates were produced. In November, the industrial trial production of liquid styrene butadiene rubber (HBS30) for 5G communication high-frequency copper clad laminates was completed, and the product reached the standard of superior products. In December, the industrial trial production of liquid styrene butadiene rubber (LBS40) for flexible resin plates was completed, and the product reached the standard of superior products.