Novel trans-1,4-polyisoprene synthesis method with high monomer conversion rate

Abstract

The invention relates to a preparation method of trans-1,4-polyisoprene (TPI). A supported titanium catalyst is used to catalyze polyisoprene polymerization, and a solution-slurry method is adopted tosynthesize powdery or block shaped trans-1,4-polyisoprene (TPI). The catalysis efficiency and monomer conversion rate are high, and the method has reached the industrialization standards. The synthesized TPI has the advantages of high hardness and excellent dynamic properties and can be easily crystallized at a room temperature. TPI has a wide application range. In a zero crosslinking phase, TPIis a thermoplastic material and is used as a medical material; in a low crosslinking phase, TPI is a thermo-elastic material and is used as a shape memory material; and when the crosslinking density exceeds a certain value, TPI becomes a rubber type high elasticity material. At present, TPI has great advantages in fields of green tires and medium-high temperature damping materials, and has a greatapplication value.

Description

technical field [0001] The invention belongs to the technical field of polymer synthesis, in particular to a preparation method of trans-1,4-polyisoprene and trans-1,4-polyisoprene prepared by the method. Background technique [0002] Trans-1,4-polyisoprene (Trans-1,4-polyisoprene), referred to as TPI, also known as synthetic Eucommia gum, has the same trans -1,4-configuration, the only difference is that natural Eucommia gum is end-capped with ester groups, while TPI, gutta-percha and balata gum are end-capped with hydroxyl groups. The chemical composition of TPI is exactly the same as that of natural rubber (NR), but the structure of the double bond in the molecular chain is opposite. The two methine groups of TPI are on both sides of the double bond axis, while the two methine groups of NR are on the double bond On the same side of the connecting axis, this leads to a large difference in performance between the two. The main performance is that NR is an amorphous polymer...

AI Technical Summary

Problems solved by technology

The catalyst efficiency of vanadium or vanadium / titanium catalytic system is low, the polymerization process is complicated, the viscosity of the reaction system is extremely high, the energy consumption and material consumption are high, and its cost and price are comparable to Eucommia gum, so it is difficult to obtain popularization and application; Catalyst bulk method polymerization has higher catalyst efficiency, but the stirring power is large, and low-temperature polymerization is required, the reaction time is long, and the late stage of the reaction is basically in the form of solid particles, so the heat of polymerization is difficult to dissipate, which can easily lead to local overheating, causing problems such as implosion, resulting in The defective rate is high, which affects the quality of the product

In addition, researchers from Zhejiang University invented a gas-phase polymerization method to prepare high-trans-1,4-polyisoprene in 2013. This method has simple condensation and separation processes, high operational safety, and less environmental pollution , but there are problems such as poor particle fluidity, difficulty in heat dissipation and easy deactivation of the catalyst

Images