Carboxylated SBR

Other polymers used in the PSA industry include synthetic polyisoprenes and polybutadienes, styrene-butadiene rubbers, butadiene-acrylonitrile rubbers, polychloroprenes, and some polyisobutylenes. With the exception of pure polyisobutylenes, these polymer backbones retain some unsaturation, which makes them susceptible to oxidation and UV degradation. The rubbers require compounding with tackifiers and, if desired, plasticizers or oils to make them tacky. To improve performance and to make them more processible, diene-based polymers are typically compounded with additional stabilizers, chemical crosslinkers, and solvents for coating. Emulsion polymerized styrene butadiene rubbers (SBRs) are a common basis for PSA formulation [121]. The tackified SBR PSAs show improved cohesive strength as the Mooney viscosity and percent bound styrene in the rubber increases. The peel performance typically is best with 24—40% bound styrene in the rubber. To increase adhesion to polar surfaces, carboxylated SBRs have been used for PSA formulation. Blends of SBR and natural rubber are commonly used to improve long-term stability of the adhesives. 

Styrene-1,3-butadiene copolymers with higher styrene contents (50-70%) are used in latex paints. Styrene and 1,3-butadiene terpolymerized with small amounts of an unsaturated carboxylic acid are used to produce latexes that can be crosslinked through the carboxyl groups. These carboxylated SBR products are used as backing material for carpets. Styrene copolymerized with divinyl benzene yields crosslinked products, which find use in size-exclusion chromatography and as ion-exchange resins (Sec. 9-6). 

Several polymers based on 1,3-dienes are used as elastomers. These include styrene-1,3-butadiene (SBR), styrene-1,3-butadiene terpolymer with an unsaturated carboxylic acid (carboxylated SBR), acrylonitrile-1,3-butadiene (NBR or nitrile rubber) (Secs. 6-8a, 6-8e), isobutylene-isoprene (butyl rubber) (Sec. 5-2i-l), and block copolymers of isoprene or... 

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... 

Non-discoloring, sulfur containing phenolic antioxidant and stabilizer that provides long-term heat stability by preventing thermo-oxidative degradation. Used for the process stabilization of polyethylene wire and cable resins for polyethylene during extruder compounding. Can also be applied in styrenic polymers, polypropylene, elastomers such as EPDM and SBR and for carboxylated SBR latex, polybutadiene rubber and polyisopropene rubber. 

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... 

Stabilization of Carboxylated Styrene Butadiene (X-SBR) Latices Carboxylated SBR latices are used as adhesives in applications where durability and flexibility are desired. Some of the major uses for X-SBR latex are in tufted carpet backing, paper coatings, wall and vinyl floor tile adhesives, and pressure-sensitive adhesives. Typically, discoloration is the first measure of the degradation of an X-SBR latex. Discoloration of a dried latex film can often be related to a loss of the physical properties and subsequently, to inferior performance in an adhesive formulation. Figure 9 illustrates the effects of adding an effective antioxidant system to an X-SBR latex on the level of discoloration as a result of static oven aging at 150°C (300°F). The addition of AO-4 alone... 

Uses Defoamer for stripping and processing carboxylated SBR and PVC emulsions for adhesives, pressure-sensitive adhesives, food pkg. ad-hesives/paper defoamer in food-contact coatings, paper/paperboard Features Readily dispersible more efficient than high-silica defoamers Regulatory FDA 21 CFR 175.105,176.170,176.180,176.200,176.210 Properties Liq. 100% act. 

Uses Crosslinking agent for carboxylated SBR latex, carbor methyl cellulose, PVA, and other water-sol. polymers water resist, aid for starch-based adhesives and coalings food-contact paper/paperboard Regulatory FDA 21 CFR 176.170,176.180 Properties Pale amber liq. water-soL sp.gr. 1.03 vise. 50 cps f.p. -3.9 C pH 4.7 cationic 12.5% total solids Storage 100 days shelf life below 32 C Polycup 1884 [Hercules]... 

The next series (Figs. 8-10) show the types of properties obtained with two different carboxylated SBR latexes tackified with the same ion-tolerant emulsion of the glycerol ester of highly hydrogenated rosin. Fig. 8 shows the property of probe tack. Both of the carboxylated latexes exhibit some inherent tack properties, but the probe tack is improved even further with increasing levels of the resin. The extent to which the tack is improved is dramatically different depending on which latex is used. Pig. 9 demonstrates the differences even further. Resin modification of Latex B which is the lower molecular weight polymer. 

Fig. 8. Polyken Tack of Various Carboxylated SBR Latexes Tackified with an Emulsion of the Glycerol Ester of Highly Hydrogenated Rosin...

Figs. 11 and 12 show two other tackifier resins for carboxylated SBR s. The polymer tackified was Latex A of the previous figures. The two resin emulsions used in these figures are the glycerol ester Of hydrogenated rosin and a hydrocarbon resin (both... 

Adhesives recommended include casein glue, epoxies, polyvinyl alkyl ether, polyacrylate (carboxylic), SBR, and polyisohutylene. 

Premium grade SLS for emulsion polymerization applications including vinyl and vinylidene chlorides, styrene and acrylic monomers. Choice surfactant for carboxylated SBR and acrylic froth applications. 

In Figure 11, dynamic mechanical properties of three carboxylated SBR latexes are shown. These three latexes show different tan 8 peak maximum temperatures and elastic... 

Guo et al. has shown the interfacial interaction in the nanocomposites between carboxylated SBR and halloysite nanotube (HNT) [106]. Lower content of HNT tends to impediment the vulcanization of SBR/HNT compounds, while higher HNT loading promotes the vulcanization presumably due to polar interactions. It is noteworthy to mention that HNT are dispersed uniformly in the matrix with strong interfacial bonding between SBR and HNT. 

BNX 1035 is a particularly effective 2Uitioxidant for polyethylene, styrenic polymers, polypropylene and elastomers such as EPDM euid SBR auid for carboxylated SBR latex, polybutadiene rubber and polyisoprene rubber. 

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