Styrene-butadiene rubber emulsion polymerisation

ISO 2322, 1996. Rubber, Styrene-Butadiene (SBR) - Emulsion polymerised - Evaluation procedure,... 

This document focuses on the main products of the European polymer industry both in production figures and in environmental impact, mainly produced in dedicated installations for the production of one specific polymer. The list of products covered is not conclusive but includes polyolefins, polystyrene, polyvinyl chloride, unsatuiated polyesters, emulsion polymerised styrene butadiene rubbers, solution polymerised rubbers containing butadiene, polyamides, polyethylene terephthalate fibres and viscose fibres. 

There are two common types of continuous reactors continuous stirred tank reactors (CSTRs) (53), and plug flow reactors (PFRs). CSTRs are simply large tanks that are ideally well-mixed (such that the emulsion composition is uniform throughout the entire reactor volume) in which the polymerisation takes place. CSTRs are operated at a constant overall conversion. CSTRs are often used in series or trains to build up conversion incrementally. Styrene-butadiene rubber has been produced in this manner. Not all latex particles spend the same amount of time polymerising in a CSTR. Some particles exit sooner than others, producing a distribution of particle residence times, diameters and compositions. 

As a result of the increasing demand for natural mbber during World War II, and the limited availability thereof, synthetic routes to general purpose (commodity) mbber production were sought. Emulsion polymerisation was successfully used to synthesise styrene-butadiene rubber (SBR) (266) for tyre production. A standardised recipe for the production of synthetic mbber is given in Table 2. 

Table 2 Recipe for the preparation of synthetic styrene-butadiene rubber GR-S (Government Rubber - Styrene) by emulsion polymerisation atS0°C ...

Amongst the polymers based on crude oil, seven groups of polymers - polyolefins (PE and PP), polystyrene (PS), polyvinyl chloride (PVC), polyethylene terephthalate (PET), emulsion polymerised styrene butadiene rubber (ESBR), polyamides (PA) and unsaturated polyester resins (UP) constitute approximately 80 % of the total consumption of polymers. 

International Institute of Synthetic Rubber Producers, I. (2002). "Best Available Techniques Production of Emulsion polymerised Styrene-Butadiene Rubber (ESBR)". 

Styrene-butadiene rubber was first prepared about 1929 in attempts to overcome the deficiencies of free-radical emulsion polymerised polybutadiene. At the time the advantages gained were not sufficient to lead to commercial use and little progress was made. In 1937, however, in correct anticipation of future difficulties in obtaining the natural material, commercial production was initiated in Germany with the product being... 

Emulsion polymerisation of a mixture of butadiene and styrene gives a synthetic rubber (Buna S GBS rubber), which is used either alone or blended with natural rubber for automobile tyres and a variety of other articles. 

Emulsion polymerisation was initially developed for producing synthetic rubber from butadiene and styrene during the Second World War. The system... 

A broad range of monomers with relatively low water solubility have been polymerised by conventional emulsion polymerisation. Acrylics, methacrylics, styrene and vinyl acetate are the most common monomers used in preparing latexes for paints, textile binders, and adhesives. Acrylic, polyester, epoxy and urethane dispersions are used in industrial coatings, where higher strength is required. Butadiene is often copolymerised with styrene in producing synthetic rubber for tyre manufacture. 

BR made by emulsion polymerisation with a free radical initiator is used as the rubber component of a high impact polystyrene and acrylonitrile-butadiene-styrene (ABS) resins. No discussion will be given on the molecular structure of this rubber. For those, who are interested in the relationship between molecular architecture and mixing behaviour, this is discussed in Section 1.1.2 on E-SBR. 

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