Carboxylated styrene butadiene rubber latex

Low absorptive capacity primary foam dressings have been produced from a carboxylated styrene butadiene rubber latex foam. The foam is bonded to a non-woven fabric coated with a polyethylene film which has been vacuum ruptured. The basic foam is naturally... 

This chapter concludes with brief reference to carboxylated rubber latexes. Further information, with references, is available in a review by Blackley [27]. Carboxylated rubber latexes contain rubbery polymers which have been modified by inclusion of a small amount of a copolymerisable carboxylic-acid monomer in the emulsion polymerization system by which they were prepared. Typical carboxylic-acid monomers are acrylic acid (XI), methacrylic acid (XII) and itaconic acid (XIII). The most industrially-important rubber latexes of this type are the carboxylated styrene-butadiene rubber latexes. Also of considerable... 

INVESTIGATION ON PRODUCTION OF CARBOXYLATED STYRENE-BUTADIENE RUBBER LATEX IN DIFFERENT POLYMERISATION REACTORS... 

Styrene-butadiene rubber latex (SBR, GRS) and acrylonitrile-butadiene rubber latex (NBR) are two of the earliest to arrive on the market. Since then, many other types have appeared, with poly(vinyl acetate) and copolymers, acrylics (generally polymers and copolymers of the esters of acrylic acid and methacrylic acids), and carboxylic-SBR types being the major products. Since latices are aqueous emulsions, less... 

Only types (l)-(4) fall within the scope of this chapter. No further reference will be made to emulsion-polymerized prolybutadiene rubbers, because they are now of little industrial significance relative to the styrene-butadiene rubbers. Poly(vinyl chloride) is discussed elsewhere in this book. Brief reference will also be made in this chapter (Section 15.5) to the production and properties of carboxylated variants of styrene-butadiene rubber latexes. It may also be noted that latexes of rubbery terpolymers of styrene, vinyl pyridine and butadiene, produced by emulsion polymerization, have long been of considerable industrial importance for the specialized application of treating textile fibres (e.g., tyre cords) in order to improve adhesion between the fibres and a matrix of vulcanized rubber in which they are subsequently to be embedded. 

Stephen, R., Ranganathaiah, C., Varghese, S., Joseph, K., and Thomas, S., Gas transport through nano and micro composites of natural rubber (NR) and their blends with carboxylated styrene butadiene rubber (XSBR) latex membranes. Polymer, XI, 858-870 (2006). 

The diffusion of some aromatic solvents (benzene, toluene, and p-xylene) through microcomposites of NR/carboxylated styrene-butadiene rubber (XSBR) latex blend membranes (70/30) was investigated by Stephen et al. Results indicated that the blend membrane exhibited unexpected diffusion behaviour, and this was attributed to the immiscibility of the two blend... 

Boonmahitthisud et al., prepared natural rubber/carboxylated styrene butadiene rubber (NR/XSBR) (80/20) nanocomposites containing different loadings of carbon nanotube (CNT) (0.1-0.4 phr) by a latex stage compounding method. The dynamic mechanical properties, in terms of tan 8 and E, of the neat 80/20 NR/XSBR blend and its nanocomposites were evaluated from —80 to 100 °C. Figure 21 shows the influence CNT loadings, on the tan 8 and E as a function of temperature for the nanocomposites [100]. 

In the past, considerable industrial interest has been shown in solid carboxylated polymers such as carboxylated styrene-butadiene rubbers (l-9) However industrial interest is now almost exclusively with carboxylated polymers in latex form Furthermore, interest is principally in the latices of carboxylated rubber latices, and of these the carboxylated styrene-butadiene rubber latices are pre-eminent. Statistics recently published for the consumption of synthetic latices of all types in Western Europe over the period 1979-QO indicate that, on a basis of dry polymer, carboxylated styrene-butadiene types make up some QP/o of the total (10). 

Since compounds of the type XVII have shown comparable activity in a number of systems including cis-polybutadiene, styrene-butadiene rubber, and ethylene-propylene rubber, they have some commercial promise, and development work on these compounds is continuing. Nevertheless, they are not completely nondiscoloring, and in certain applications, particularly carboxylated styrene-butadiene latex films, yellow discoloration caused by the antioxidant is a serious drawback. We therefore turned our attention to ortho-linked compounds derived from 2,4-dialkylphenols. 

The largest-volume synthetic rubber consumed is styrene-butadiene rubber (SBR). In 2003, SBR solid rubber accounted for 41 percent of all synthetic rubber. If SBR latex and carboxylated SBR latex are included, its share increases to 55 percent. The major application of solid SBR is in the automotive and tire industry, accounting for approximately 70 percent of the use. Therefore, SBR has been tightly tied to the tire business.25... 

A latex adhesive is necessary to bond the tufts into the primary backing, adhere the individual fiber strands in the yarn tufts together so they don t separate and "piU at the carpet surface, and attach the secondary backing to this primary structure. This is accomplished almost exclusively by carboxylated styrene-butadiene latex containing 400 or more parts per hundred parts of rubber of a mineral filler. In addition to economics, this filler hel s provide density and stiffness to the carpet structure for the desired hand." Feld ar used to he the filler of choice, but less expensive calcium carbonate has replaced it in most instances. 

Waterborne dispersed polymers include both synthetic polymer dispersions and natural rubber. Synthetic polymer dispersions are produced by emulsion polymerization. A substantial part of the synthetic polymer dispersions is commercialized as dry products these include SBR for tires, nitrile rubbers, about 10% of the total PVC production, 75% of the total ABS and redispersable powders for construction materials. Carboxylated styrene-butadiene copolymers, acrylic and styrene-acrylic latexes and vinyl acetate homopolymer and copolymers are the main polymer classes commercialized as dispersions. The main markets for these dispersions are paints and coatings, paper coating, adhesives and carpet backing. 

One method (117) of producing cellular polymers from a variety of latexes uses primarily latexes of carboxylated styrene-butadiene copolymers, although other elastomers such as acrylic elastomers, nitrile rubber, and vinyl polymers can be employed. 

Initially starches and natural rubber latex were used as binders for improved tuft bind. They were replaced in the late 1950s by carboxylated styrene-butadiene dispersions (XSB). XSB emulsion polymers are very cost effective and easy to formulate, and they have become the working horse of the carpet backing industry and are almost exclusively used today. 

Over the years, it is fair to say that virtually every type of polymer available in dispersion form has been tried for use in the backing compound for tufted carpet. However, because of its versatility and cost-effectiveness, it is the carboxylated styrene-butadiene (XSB) polymer dispersions that hold the major share of this business today with an estimated 95 % of the volume sold in 1999, the remaining volume being shared by ethylene-vinyl acetate, polyvinyl chloride and polyurethane dispersions. During 1999, the U S carpet industry consumed approximately 490 kt wet dispersion, of which 463 kt were XSB [4]. The majority of the XSB is supplied direct to the carpet mills by the three major dispersion producers BASF, Dow Chemical, Omnova, with a minor proportion being supplied by so-called re-sellers or compounders such as General Latex, Polymer Products, Southeastern Latex and Textile Rubber. 

Dispersions of copolymers of butadiene with acrylic acid or methacrylic acid in aqueous potassium hydroxide have been mentioned in the patent literature" as a dip for adhering rayon tire cord to rubber. The effect is most evident when carboxyl groups are present in the adhesive, the tie cement, and the cover stocks. The adhesive may be applied as latex, aqueous dispersion, or cement. A patent issued to the Dunlop Company Ltd." describes the use of a styrene-butadiene-itaconic acid copolymer with Gen-Tac Latex (GenCorp) in formulating an RFL (resorcinol formaldehyde latex) type adhesive for bonding a natural rubber compound to Nylon 66 and rayon tire cords. Brodnyan" also claims carboxylic adhesives for rayon, nylon, and Dacron cords. In this case, the tire cords were treated with a mixed polymer latex containing resorcinol-formaldehyde condensate, a butadiene-vinyl pyridine copolymer, an SBR copolymer, and a multifunctional copolymer from methyl acrylate, 2-hydroxy propyl methacrylate, and acrylic acid. A different approach was reported by Badenkov" whereby rayon or nylon tire cords were coated with... 

Carboxylic elastomers have also been prepared by the addition of a carboxyl-bearing molecule such as thioglycollie acid, maleic anhydride, or acrylic acid to rubber in solvent, on the mill, or in latex. The preparation of a carboxylic polymer from a butadiene-acrylonitrile copolymer in an internal or Banbury mixer has been mentioned in the adhesives patent literature. The carboxylation of vulcanized natural rubber and of butadiene-styrene copolymers, including reclaimed stocks of these elastomers, by treatment with maleic an-... 

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