Rubber-based adhesive physical

With rubber base adhesives, it is necessary to prevent their properties from changing during service life. Oxidative changes induced by thermal, ozone exposure and UV light can dramatically affect service life of rubber base adhesives. More precisely, the rubber and the resin are quite susceptible to oxidative degradation. Environmental and physical factors exert detrimental effects on rubber base adhesive performance. These effects can be mitigated by the incorporation of low levels of stabilizers during the fabrication process of the adhesive. 

Rubber based adhesives are used in a myriad of applications which are familiar to the consumer. Tile and paneling adhesives are examples of these adhesives used in home construction. The largest use of mbber-based adhesives is in laminated furniture manufacmre. Representative physical properties of mbber-based adhesives are shown in Table 27.4. The adhesives are characterized as having low to moderate shear strength and high peel strength. 

The difference between plasticizers and tackifiers is somewhat arbitrary and the effect of this difference is described below in the section on Physical Properties. Plasticizers are typically lower in molecular weight and melting or softening point than are tackifiers. Hydrocarbon oils including aromatic, naphthenic, and paraffinic are commonly used with rubber-based adhesives. Phthalates, such as dioctyl phthalate or dibutyl phthalate, are more typically used in small amounts with acrylics. Since plasticizers are usually low molecular weight compounds, there is often more latitude in the chemical types that will be compatible with the base pol5mier because of the contribution from entropy of mixing. 

The viscoelasticity and surface tension of adhesives are physical properties that are independent of the specific chemical composition. Therefore, the relations discussed for rubber-based adhesives are also valid for polyacrylates [218] and other elastomeric bases. 

The information is limited to the most important materials, metals, plastics, (thermoplastics, thermoset materials, foams), ceramics, glass and their possible combinations. For papers, cardboards, wood, rubber polymers, usually physically setting systems (solvent-based, dispersion, hot-melt adhesives) are utilized. In these cases, the adhesive selection with regard to the manufacturing conditions and demands is of less problematic nature. 

Phenolic based adhesives are outstanding in their wetting characteristics and strength. In the unmodified form, however, they tend to be brittle. To overcome this problem, phenolic based adhesives usually contain a rubber modifier to increase the crack resistance of the adhesive. The first modified phenolic contained polyvinyl butyral and was known as the "Redux" adhesive. Many modern phenolic adhesives contain nitrile rubbers (copolymers of acrylonitrile and butadiene) as the modifiers. An example of a phenolic based film adhesive is AF-30 which is listed in Table 1 along with its physical properties. This film... 

The concept of rubber reversion protection by using biscitraconimidomethylbenzene, trade name Perkalink 900, is discussed. The advantages of using this chemical in NR based adhesion compounds was examined. The effects of its use on adhesion to textiles, cure characteristics physical, mechanical and thermal properties are discussed. 14 refs. 

The conunon polymers for plastics, rubbers and fibers have been produced at a large industrial scale. It appears difficult to modify them from the early stage of the preparation route. Currently, most of modificatimis either via physical methods or via chemical treatments are based on their structure—property relationships. The specific functimial polymers for coatings, adhesives, adsorption resins and filtration membranes occupy a relatively small market, and their modifications often start from monomer synthesis. 

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