Polychloroprene rubber adhesives: applications and properties

Further information on rubber-based adhesives is to be found in specialized articles Natural Rubber-Based Adhesives, Nitrile Rubber Adhesives, Polychloroprene Rubber Adhesives Applications and Properties and Polychloroprene Rubber Adhesives Modifiers and Additives. 

It is interesting to compare the properties of NBR adhesives with those of another polar rubber Polychloroprene rubber adhesives applications and properties. 

Most Rubber-based adhesives may be cured by a sulphur-based vulcanizing system (see Rubber-based adhesives compounding), however, as mentioned in Polychloroprene rubber adhesives applications and properties, CR adhesives are cross-linked by various reactions involving the labile chlorine atoms in the repeat unit. This is reflected in the additives used, as discussed below. ... 

During the World War II, several new synthetic elastomers were prodnced, and new types of adhesives (mainly styrene-butadiene and acrylonitrile copolymers (see Nitrile rubber adhesives)) were manufactured to produce adequate performance in joints produced with new difficult-to-bond substrates. Furthermore, formulations to work under extreme enviromnental conditions (high temperature, resistance to chemicals, improved resistance to ageing) were obtained using polychloroprene (Neoprene) adhesives (see Polychloroprene rubber adhesives applications and properties and Polychloroprene rubber adhesives modifiers and additives). Most of those adhesives need vnlcanization in order to perform properly. 

Polychloroprene rubber (CR) is the most popular and versatile of the elastomers used in adhesives see Polychloroprene rubber adhesives applications and properties and Polychloroprene rubber adhesives modifiers and additives. 

The polychloroprene latex determines the initial tack and open time, the bond-strength development and hot bond strength, the application properties, and the adhesive s viscosity. Because most latices have low viscosities by compounding, most of the water-borne polychloroprene rubber adhesives are sprayable. Thickeners such as fumed silicas can be added to increase viscosity and thixotropy. 

Several elastomers can be used in rubber-based adhesives. The elastomer provides the backbone of the adhesive, so the main performance of the adhesive is provided by the rubber properties. However, several specific properties for application are imparted by adding other ingredients in the formulations. The most common elastomers used in rubber-based adhesives are natural rubber (NR), butyl rubber (BR) and polyisobutylenes, styrene-butadiene rubber (SBR), nitrile rubber (NBR) and polychloroprene rubber Neoprene) (CR). 

Solvent cements encompass a wide range of performance properties, from the simple natural rubber based cements which are widely used for low performance applications in homes and schools to the structural applications of contact adhesives based on polychloroprene and reactive phenolic resins. 

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