Polyurethane Rubber latex

The entire installation is finished with a carpet of synthetic grass, which comprises usually a woven polypropylene lattice in which tufts of green polypropylene fibre or filament are fixed. The lattice is sealed on the under-side with a bonded film—which keeps the tufts in place and may be made from polyethylene, polyurethane, rubber latex, or vinyl plastisol. 

Another problem is that some persons are allergic to the proteins often found in natural rubber. This can be avoided by the use of a polyurethane condom. Unfortunately, as now made, these are more likely to tear (7-9% of the time) than the rubber latex condoms (2% of the time).65 It has been suggested that they be made of guayule rubber latex, which is free of the allergens.66 Thermoplastic elastomers, such as polystyrene-6-(ethylene-co-butene)-Apolystyr ene have been used to make gloves that are more resistant to ozone than those made of natural rubber.67 These should resist aging better than those made of natural rubber. It should be possible to mold a condom without holes from a thermoplastic rubber. 

The development of plastics reflects economic history. Restrictions on imported rubber latex, wool, sUk and other natural materials to Europe during World War II stimulated the development of synthetic alternatives. Between 1935 and 1945, many new polymers were introduced including polyethylene, polyamides, poly (methyl methacrylate), polyurethanes, poly (vinyl chloride). 

The elastomeric group of adhesives is based on natural rubber latex and its derivatives or totally synthetic rubber known as SBR (styrene butadiene rubber). There is now a wide range of synthetic rubber adhesives based upon SBR including nitrile and butyl rubber. Another elastomeric adhesive is the versatile polyurethane rubber group. 

The Lambda series of Medicaflex is a polyurethane-based TPE polymer that exhibits low modulus characteristics with high tear strength and abrasion resistance. Those listed in the tables have passed USP Class VI compatibility tests and have been used as replacements in some natural rubber latex and silicone rubber applications. The polymer has been applied to uses such as catheters, tubing and films where softness, low durometer hardness, low modulus or high elongation are needed (Tables 4.3, 4.12, and 4.13). 

Cellulose acetate natural rubber (latex), polyisobutylene rubber, neoprene rubber, polyvinyl acetate, ethylene vinyl acetate, polyacrylate (carboxylic), cyanoacrylate, polyamide (versamid), phenoxy, polyester + isocyanate, nitrile-phenolic, polyurethane, and resorcinol-formaldehyde. 

Water-based dispersions or emulsions such as polyvinyl acetate, acrylics, polyvinyl chloride and polyvinyl alcohol with plasticizers and tackifiers. In addition, this range can include urea formaldehyde and phenolic adhesives, resins, natural adhesives produced from starch, dextrin, casein, animal glues (see Polyvinyl alcohol in adhesives, Phenolic adhesives single-stage resoles. Phenolic adhesives two-stage novolacs. Animal glues and technical gelatins) and rubber latex (see Emulsion and dispersion adhesives). Solvent-free 100% solids such as polyurethane. Hot melt adhesives include Ethylene-vinyl acetate copolymers, polyolefins, polyamides, polyesters with tackifiers and waxes. More recent additions include cross-linkable systems. 

Varghese, S., Gatos, K.G., Apostolov, A.A., KargCT-Kocsis, J. Morphology and mechanical properties of layered silicate reinforced natural and polyurethane rubber blends produced by latex compounding. J. Appl. Polym. ScL 92, 543-551 (2004)... 

Aft r a low productive decade, the Mobay Corp. was formed by Bayer and Monsanto for the production of polyurethanes in the U.S. in 1953. However, the first polyester-based polyurethane foam disintegrated in humid air and could not compete with rubber latex foam. This difficulty was overcome by the use of hydroxyl terminated polyethers instead of polyesters. 

Thermoplastic elastomer free of latex and rubber additives. Adequately prevents transmission of HIV Natural latex and must be avoided by patient with ACU Trojan brands contain carbamates but no mercaptobenzothiazole, thiurams, or anti-oxidants. Adequately prevents transmission of HIV Vaginal condom made of polyurethane. No latex, MBT, thiurams, carbamates or thioureas. Adequately prevents transmission of HIV... 

Mouth PrOtOCtOrS. The widespread growth of contact sports has accelerated the use of mouth guards (34,35). Guards may be produced from natural rubber, poly(vinyl chloride), poly(vinyl acetate-co-ethylene), or polyurethane materials. Customized guards are often fabricated from poly(vinyl acetate-co-ethylene) blanks, soft acrylic dough, liquid rubber latex, polyurethane, and laminated thermoplastic (36,37). Over the counter protectors usually fit poorly, in contrast to dimensionally stable and comfortable, customized mouth protectors. 

Polymer type Polyolefins Polyolefins, olefin based TPE s, flexible PVC, polyesterether TPE, polyurethanes, natural rubber latex, and natural rubber compounds... 

Fig. 5. Dynamic compression characteristics of cored rubber latex, conventional moulded polyurethane and high resilience moulded polyurethane foam.

Large amoimts of calcium carbouate, almniua trihydrate, aud barite are used to fill foam imderlay for carpets. The base polymers are rubber, syuthetic thermoplastic and polyurethane in latex form. The fillers serve two fimctions - to add weight so that the carpet lies flat on the floor and does not shift with traffic, and to reduce flammability. 

Shoe adhesive Polyurethane, phenol, SBR, rubber latex... 

Water-based dispersion adhesives consist of oligomers dispersed in water with surfactants as dispersing agents and stabilizers. Before dispersions, natural rubber latex and casein were used to manufacture such adhesives. Currently, polyvinyl acetate (PVAc) and polyacrylate serve as synthetic base polymers for water-based PSA, while polychloroprene and thermoplastic polyurethane serve the same purpose for water-based contact adhesives. 

In 1994, the worldwide consumption of rubber was approximately 14.5 million tons a year, of which about 40% consisted of natural rubber. Natural rubber is produced as latex by tropical rubber trees (Hevea brasiliensis). It is processed locally and therefore the quality of natural rubber fluctuates remarkably [ 140]. Due to increasing demand for rubbers, combined with a decreasing production capacity in Asia and a vast increase in labor costs, the price of natural rubber is still rising sharply. In 1990-1994, the average price of natural rubber was about 0.38 /lb, while in 1996 it was already over 0.80 /lb. The remaining 60% of the articles were manufactured from synthetic petroleum-based rubbers such as isoprene rubber, styrene-butadiene rubber, chloroprene rubber and polyurethanes. The quality of synthetic rubbers is constant, and their price varies between 2 and 5 US per kilogram [137-140]. 

A method of manufacturing rubber articles by pouring a compounded latex into an absorbent hollow mould the skin of rubber thus formed is removed, dried and vulcanised. The term is also apphed to the pouring into moulds of liquid polymer systems based on silicone or polyurethane elastomers. 

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