Лако-красочные материалы — производство

While there are significant differences between grades of polychloroprene elastomers due to molecular weight differences and crystallinity characteristics, by and large, processing and performance properties may include:

Superior green strength Applying a thin coat of either water-based or solvent-based adhesive onto each of the substrates to be bonded, drying to a tacky-to-the- touch condition, and mating the surfaces with moderate pressure provides excellent contact bond strength. Often this early strength enables immediate processing in the next part of the assembly, or packaging for shipment.

High ultimate strength Although polychloroprene elastomers can be processed as pressure sensitive adhesives, which are typically low strength applications, typical usage is for high strength requirements. On some surfaces, with a reacted phenolic resin as a formula ingredient, a lap shear strength in excess of 70 kg/cm[9] can be achieved.

Wide surface compatibility The high polarity of the base elastomer aids in devel­oping adhesion to virtually all high polarity surfaces. Solvent-based products often develop good adhesion to low polarity surfaces such as polyolefins and other plastic substrates.

Thermoplastic or thermosetting While many contact bond applications require no curing process because an extra strength requirement is not present, in certain formulations polychloroprene will provide ambient cure for improved proper­ties, and can be cured by several different mechanisms for high performance properties. Ambient cure systems are typically one component, while high performance formulations are often two-part systems, or one-component sys­tems cured in elevated temperature conditions.

Resistance to moisture, chemicals, and oils Service conditions and assembly config­uration often play a part in total resistance to end use environment, but poly — chloroprene exhibits excellent performance for most conditions. Constant immersion in any of these materials is not recommended.

Resistance to temperature Depending on the degree of cure, if required, polychlor — oprenes will typically provide temperature resistance in the —50°C to 150°C range, with special formulations capable of even wider ranges.

Resistance to aging While compounding for outdoor exposure is recommended to provide superior performance, the presence of the chlorine atom in the mole­cule helps provide better resistance to aging than most synthetic elastomers.

applications for hose and belt manufacture, and for rubber membrane roofing, still recom­mend a solvent-based product. For applications where high strength is not as big a factor, such as foam fabricating, latex compounds are preferred, sometimes using a two-part system with an acid catalyst to speed processing and bond development. Many leather goods markets, such as belts and shoes, prefer polychloroprene contact bond adhesives because of the fast processing cycles. Polychloroprene adhesives are used to manufacture recreational vehicles, kitchen counter tops, office furniture and partitions, truck and trailer bodies, plastic and composite wood bonding, gasket and trim bonding, floor tile mastics, and many other applications. These polymers can be converted into heat and solvent reactivatible films.