이소부틸렌-이소프렌 공중합체

이소부틸렌-이소프렌 공중합체 C화학적 특성, 용도, 생산

개요

A synthetic copolymer containing from 0.5 to 2.0 molar percent of isoprene, the remainder, respectively, consisting of isobutylene. It is prepared by copolymerization of isobutylene and isoprene in methyl chloride solution, using aluminum chloride as the catalyst. After completion of polymerization, the rubber particles aretreated with hot water containing a suitable food-grade deagglomerating agent, such as stearic acid. Finally, the coagulum is dried to remove residual volatiles.

화학적 성질

Butyl rubber has the chemical resistance characteristic of saturated hydrocarbons. Oxidative degradation is slow, and the rubber may be further protected by incorporating antioxidants. Isobutylene is the major component of bulk rubber. It provides good aging resistance and low gas permeability. Isoprene, a minor component, enhances vulcanizability.

용도

Butyl rubber is formed from the polymerization of isobutene (isobutylene) with small amounts of chloroprene, isoprene, or butadiene and may be halogenated. The reaction is carried out in a closed system with an aluminum chloride catalyst. Butyl rubber is highly impervious to gases, which makes it the rubber best suited for inner tubes and tires, air chambers, adhesives, and dielectrics. Isobutene is an anesthetic and asphyxiant gas and can be hazardous in concentrations high enough to produce asphyxia. At these concentrations, explosion is an additional hazard.

생산 방법

The bulk of butyl rubber is made by a slurry process using aluminum chloride at 98–99°C and methyl chloride as a diluent. The extremely rapid reaction is unique, and proceeds via cationic polymerization to completion at 100°C in less than a second. Butyl rubber may be vulcanized by three basic methods: accelerated sulfur vulcanization, cross-linking with dioxime and related dinitroso compounds, and polymethylol– phenol resin cure. Halogenated butyl rubber allows broadened vulcanization latitude and rate, and enhanced covulcanization to general-purpose elastomers while it maintains the unique attributes of the basic butyl molecule.

제조 방법

Commercial butyl rubbers generally contain 1-3 mole % isoprene. In a typical process, a solution of the monomers in methyl chloride is pre-cooled to -lOO??C and then fed continuously into the base of a reactor together with a solution of aluminium chloride (initiator) in the same diluent. The reaction is highly exothermic and in order to maintain the temperature at -100??C the reactor is fitted with a powerful stirrer and cooling coils containing liquid ethylene. The polymer forms as a granular slurry which is displaced continuously from the top of the reactor. The slurry passes into a flash tank where it is vigorously agitated with hot water. This treatment deactivates the initiator and extracts water-soluble products. At the same time the diluent and unreacted monomers are flashed off and are purified and re-used. Also at this point a lubricant and an antioxidant are introduced into the polymer. The lubricant, usually zinc stearate, prevents agglomeration of wet crumb and the antioxidant, usually phenyl-p-naphthylamine, reduces degradation during drying operations. The slurry then passes to a screen where wet polymer crumb is isolated. The crumb is dried at about 95-170??C, fed through an extruder and then hot milled. The object of these last operations is to compact the polymer and remove all traces of residual water.
In butyl rubber the isoprene is present as random l,4-units and the copolymer thus has the following form:

공업 용도

Butyl rubbers have outstanding impermeabilityto gases and excellent oxidation andozone resistance. The chemical inertness is furtherreflected in lack of molecular-weightbreakdown during processing, thus permittingthe use of hot-mixing techniques for betterpolymer/filler interaction.

Advantages

Butyl rubber is chemically resistant to non-oxidizing dilute mineral acids, salts and alkalis, and a good chemical resistance to concentrated acids, except sulfuric and nitric acids. Moreover, it has a low permeability to air and an excellent resistance to aging and ozone. However, it is readily attacked by oxidizing chemicals, oils, benzene, and ketones and as a general rule it has also poor chemical resistance to petroleum and its derivatives and many organic chemicals. Moreover, butyl rubbers are sensitive to UV-irradiation (e.g., sunlight exposure). As with other rubbers, its mechanical properties can be largely improved by the vulcanization process.

이소부틸렌-이소프렌 공중합체 준비 용품 및 원자재

원자재

준비 용품

이소부틸렌-이소프렌 공중합체 공급 업체

공급자	전화	이메일	국가	제품 수	이점
Henan Fengda Chemical Co., Ltd	+86-371-86557731 +86-13613820652	info@fdachem.com	China	7786	58
Shanghai Daken Advanced Materials Co.,Ltd	+86-371-66670886	info@dakenam.com	China	15928	58
Henan Tianfu Chemical Co.,Ltd.	+86-0371-55170693 +86-19937530512	info@tianfuchem.com	China	21691	55
Chongqing Chemdad Co., Ltd	+86-023-61398051 +8613650506873	sales@chemdad.com	China	39916	58
career henan chemical co	+86-0371-86658258 15093356674;	factory@coreychem.com	China	29826	58
Shaanxi Dideu Medichem Co. Ltd	18192627656	1012@dideu.com	China	3422	58
Dayang Chem (Hangzhou) Co.,Ltd.	571-88938639 +8617705817739	info@dycnchem.com	CHINA	52867	58
ShanDong Look Chemical Co.,Ltd.	+8617653113219	sales01@sdlookchemical.com	China	2739	58
PT CHEM GROUP LIMITED	+86-85511178 +86-85511178	peter68@ptchemgroup.com	China	35453	58
Nanjing Bicbiotechnology Co., Ltd	+86-2552131256 +86-18251840740	sales@bicbiotech.com	China	6000	58

이소부틸렌-이소프렌 공중합체 관련 검색: