A kind of preparation method of coordination cross-linked rubber containing crystal water metal salt

Abstract

The invention relates to a coordination crosslinking method of rubber, in particular to a method for preparing rubber from a metal salt containing concentration water through coordination crosslinking. In preparation, after the rubber is fed in mixing equipment to be plastified, a coordination crosslinking agent, an aging resisting agent, a reinforcing agent, a coupling agent and a plasticizer are sequentially added and uniformly mixed to obtain a low-temperature rubber compound; after the low-temperature rubber compound is mixed, a water absorbent is added, the mixture is continuously and uniformly mixed, and a high-temperature rubber component is obtained; the high-temperature rubber compound is fed in vulcanizing equipment, is preheated for 0.5-2 min at a temperature of 170-200 DEG C, and is then vulcanized for 5-35 min under 5-20 MPa, and the coordination crosslinking rubber is obtained. High-temperature mixing is adopted, so that the fusion and ionization probability of the metal salt taken as the coordination crosslinking agent is improved remarkably, and the hydrogen bonding force of free crystallization water is weakened; oxides are added to absorb the free crystallization water, so that the foaming rate during the high-temperature coordination crosslinking process is reduced remarkably, the ionization of the metal salt can be promoted, the coordination crosslinking efficiency is improved, and the consumption of the metal salt taken as the coordination crosslinking agent is beneficial for reduction.

Description

technical field [0001] The invention relates to a coordination crosslinking method of rubber, in particular to a preparation method of coordination crosslinking rubber containing crystal water metal salt. Background technique [0002] Crosslinking plays an important role in improving the properties of rubber. The traditional sulfur-containing system or peroxide covalent crosslinking can obtain polysulfide bond crosslinking structure and C-C bond covalent crosslinking structure, respectively. Compared with covalent crosslinking, coordination crosslinking obtains a coordination bond crosslinking structure, which has the following advantages: (1) The coordination bond can simultaneously have the good heat resistance of the C-C bond and the stress resistance similar to the polysulfide bond. (2) The coordination cross-linking structure can endow the coordination cross-linking rubber with reversible thermoplastic high elasticity, making it thermoplastic, which is beneficial to re...

AI Technical Summary

Problems solved by technology

[0004] However, crystallization water exists in the metal salt coordination crosslinking agent, which brings the following fatal problems to the existing coordination crosslinking rubber method: (1) crystallization water will break away from self-association at high temperature to form a polar phase or dissociate from the metal salt The surface forms a polar liquid film through hydrogen bonding, so it is easy to deteriorate the compatibility between the metal salt and the rubber, making it difficult to blend the two uniformly; (2) change the surface energy so that the coordination crosslinking mainly occurs on the surface of the inorganic salt, Cause uneven coordination crosslinking reaction, slow rate and low efficiency; (3) Crystal water will volatilize during high temperature vulcanization, causing the vulcanization system to foam and changing the mechanical properties of the product

In addition, the existing coordination crosslinking rubber method still has the following common technical defects that need to be overcome: (1) The amount of coordination crosslinking agent is large, usually more than 20 parts by weight, so the product is relatively brittle, and it is difficult to achieve high strength and high toughness (2) The activation energy of the coordination cross-linking reaction is relatively high, so a high-temperature coordination cross-linking vulcanization process is required

The above-mentioned problems are the reasons why it is still difficult for coordination crosslinked rubber to obtain ideal industrial applications.

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