Neoprene glues

Thiuram mix, 1% petrolatum. Rubber parts in neoprene glues... 

Para-tertiary-buty pheno formaldehyde resin (PTBP-F-R) is a polycondensate of para-tertiary-butylphenol and formaldehyde. Major occupational sources are neoprene glues and adhesives in industry, in the shoemaking and leather industry or in car production. It is also used as a box preservative in box and furniture manufacture, and in the production of casting moulds, car-brake linings, insulated electrical cables, adhesives, printing inks and paper laminates. Para-tertiary-butyl-phenol is the sensitizer. 

Uses pol erization inhibitor added to polyurethane resins and Neoprene glues for use, e.g., in the shoe industry A... 

PTBP had been known to cause contact dermatitis in shoe manufacturers, and wearers, and in automobile assemblymen (Kahn 1970). PTBP formaldehyde resin (PTBPFR) is also a contact sensitizer, present in neoprene adhesives used in the manufacture of car seats, roof linings, and care interiors. Depigmentation on the hands and forearms were observed in 11 of 99 British automobile factory workers who were exposed to a PTBFR glue without wearing protective gloves (Calnan and Cooke 1974). Malten (1984) attributed the leukoderma to excess PTBP in the glue. 

Ethylbutylthiourea is contained in glues, mainly the neoprene type. 

Only the water based adhesives and glues such as vinyls, acrylics, some thermosetting glues such as UF, some fluid epoxies may be sprayed with airless spray. However, we may mention here the use of airless to spray a dispersion contact neoprene adhesive of high viscosity - 50,000 mPas - with a coverage of 100 g/m. ... 

The situation did not change until 1942, soon after the start of World War II. At that time, a critical shortage of natural rubber developed because it was allocated chiefly for the war effort. Neoprene was chosen as a replacement for natural rubber in adhesives because it was the only other synthetic rubber available. Animal glue and other water-soluble materials available at the time were unsatisfactory because of their slow drying rates, poor adhesion to many surfaces, inflexible films, and rusting of metals. The two Neoprene polymers available at the time were Neoprene GN, a general purpose type, and Neoprene CG, a fast-crystallizing type. Both are copolymers of chloroprene and sulfur which contain a thiuram disulfide modifier. 

Terpene phenolic resins, such as Schenectady s SP-560 or Occidental s Durez 12603, are also often used in Neoprene adhesives. They are nonreactive and thermoplastic in nature and so provide longer open tack time and a softer glue line than the f-butyl phenolics, but offer less hot cohesive strength. Terpene phenolic resins are often used in combination with a polyisocyanate curing agent, such as Bayer s Desmodur RF, in a two-part adhesive system to obtain better hot bond strength. 

These materials are based on polymer latexes made by emulsion polymerization. They flow easily while the continuous water phase is present and dry by evaporation of the water, leaving behind a layer of polymer. In order that the polymer particles coalesce to form a continuous joint and be able to flow to contact the adherend surfaces, the polymers used must be above their glass transition temperature at use temperature. These requirements are similar to those for latex paints, so it is not surprising that some of the same polymers are used in both applications, for example, styrene-butadiene copolymers and poly(vinyl acetate). Nitrile and neoprene mbbers are used for increased polarity. A familiar example of a latex adhesive is white glue, basically a plasticized poly(vinyl acetate) latex. Latex adhesives have displaced solvent-based adhesives in many applications because of their reduced pollution and fire hazards. They are used extensively for bonding pile and backing in carpets. 

The most typical adhesive solvents are those based on elastomers, compounds characterized by the fact that they have a strong natural adhesiveness, especially in respect of themselves (the phenomenon of self-adhesion, the instantaneous adhesion of two films of glue after almost total evaporation of the solvent, is the basis for the composition of the contact glues especially neoprene-based (Fletcher 1971)). The basic chemical composition of neoprene synthetic rubber is polychloroprene (O Fig. 14.6). The polymer structure can be modified by copolymerizing chloroprene with, for example, 2,3-dichloro-1,3-butadiene to yield a family of materials with a broad range of chemical and physical properties. 

Uses Defoamerfor latex paints based on acrylic, S/B, PVAc, and EVA latexes defoamerfor acrylics, P Ac, PVOH, neoprene, and nat. latexes for adhesives and glues... 

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