2results about How to "Low gel content" patented technology

The present application relates to the field of polymer manufacturing, and particularly relates to a long-chain branched modification method of rare earth isoprene rubber and / or butadiene rubber, comprising the following steps: S1. performing solution polymerization of isoprene and / or butadiene and isoprene in a non-polar solvent in the presence of a rare earth catalyst to obtain a glue solution containing active polymer molecular chains; S2. when the conversion rate of the polymerization reaction reaches 95% or more, adding a compound branched modifier to the glue solution to perform a branched reaction; wherein the compound branched modifier comprises at least one of a chloride and an alkyl halide and at least one selected from ether compounds and tertiary amine compounds. The branched modifier used in the present application has a strong branching effect, and has good solubility so as to achieve uniform mixing at a molecular level in the glue solution, significantly alleviates the gel side reaction, reduces the gel content, narrows the molecular weight distribution, significantly improves the raw rubber performance, and improves the product uniformity.

This invention discloses a highly elastic and resilient vinyl elastomer and its preparation method. The method includes: solution polymerization of ethylene, comonomers, and functional monomers in the presence of a catalyst to obtain a vinyl copolymer precursor; subsequently, dissolving the precursor in an organic solvent, adding a ring-closing reagent to perform an intramolecular ring-closing reaction, and adding a monofunctional end-capping agent to terminate the reaction; and obtaining the vinyl elastomer after separation, washing, and drying. By controlling the monomer feed in stages, a gradient structure is formed in the molecular chain, with ethylene-rich segments at both ends and α-olefin-rich segments in the middle. Combined with the intramolecular ring-closing structure, topological constraints are introduced, significantly improving the material's elastic recovery performance while maintaining thermoplastic processability. The resulting material exhibits a resilience of over 63%, a compression set of less than 24%, a melt strength of over 7.1 cN, and a gel content of less than 1.2%.