Sole-attaching adhesive

D 2558 Test Method for Evaluation Peel Strength of Shoe Sole Attaching Adhesives... 

ASTM D2558-69 (1984) (withdrawn 1990) Standard test method for evaluating peel strength of shoe sole attaching adhesives. 

Evaluating Peel Strength of Shoe Sole Attaching Adhesives, Test for (D 2558) Determining Durahiliiy of Adhesive Joints Stressed in Peel, Practice for (D 2918) Floating Roller Peel Resistance, Tbst for (D 3167)... 

During World War II, polychloroprene was chosen as a replacement for natural rubber because of its availability. Two copolymers of chloroprene and sulphur which contain thiuram disulphide were available (Neoprene GN and CG). One of the first successful applications of these polychloroprene adhesives was for temporary and permanent sole attachment in the shoe industry. However, these polychloroprene cements show a decrease in viscosity on ageing and a black discolouration appears during storage in steel drums. Discolouration was produced by trace amounts of hydrochloric acid produced by oxidation of polychloroprene... 

Footwear is a sizable niche for polyurethane adhesives that are used to attach the soles. Polyurethane adhesives compete primarily with neoprene-based adhesives and have replaced much of the neoprene volume due to improved performance. However, the overall market has declined as U.S. manufacturers have moved production overseas. 

Aerobic adhesives, on the other hand, were designed to be used as the sole attachment device. They are as fast as many instant glues yet durable enough to be considered a chemical fastener, replacing the need for mechanical fasteners, in many instances. 

There is a basic difference between the bonded inserts, which rely solely on adhesion for their attachment to the parent component, and the embedded inserts, where the attachment to the composite member is based on mechanical interlocking or entrapment, although the latter are often secured by bonding for convenience. 

Film overlay laminations (furniture) and sole attaching (footwear) are other applications for polyurethane adhesives (Table 15). 

Neoprene, or polychloroprene, was the first synthetic elastomer used by the adhesives industry, and is one of the most versatile materials ever developed as a backbone for elastomeric adhesives. Neoprene combines rapid bond strength development with good tack or auto-adhesion, and resistance to degradation by oils, chemicals, water, heat, sunlight, and ozone. It is popular in numerous areas such as shoe sole attachment, furniture construction, automobile assembly, and a variety of construction applications. 

The fast crystallizing types are widely used in shoe sole attachment, adhering decorative high pressure laminates and automotive trim and in many other industrial applications. A general purpose adhesive formulation is presented in Table 2. 

The peel strength varies according to the types of adhesives. They are very low (200-800 g/cm) for PSAs, up to 100 N/cm for PU adhesives used for shoe soles attachment (peel strength of shoe soles attachment may be measured according to ASTM D 2558). 

The sole attaching apphcation also needs the PUR adhesive due to its high initial strength, its high heat resistance and cold flexibility, excellent water resistance and fast chemical crosshnking as well as fast setting. 

A typical composition of a solvent-borne polychloroprene adhesive for upper to sole attachment is given in Table 51.2. 

Abbott SG (1992) Solvent-free adhesives for sole attaching. SATRA Bull 109 (October issue)... 

Shoe adhesives. CR adhesives are used for the permanent attachment of shoe soles. For difficult-to-bond sole materials (plasticized PVC, EVA foaming soles, thermoplastic rubber, SBR) graft polymer solutions of Neoprene AD-G combined with a polyisocyanate provide a good adhesion. Another major area for CR contact adhesives is the manufacture of leather goods, particularly leather shoe sole bonding and belt lamination. 

Polychloroprene plus a phenolic is a contact adhesive to bond flooring to concrete or wood, to attach soles to footwear, and to bond vinyl seats and roofs to automobile bodies. 

Adhesives must function solely through surface attachment. Therefore, the nature of the condition of the adherend surface is crucial to the formation of strong and durable bonds. By surface we usually mean that region of a material which interacts with its surroundings. There is some region of a bonded assembly where the adhesive and the adherend interact, but only rarely is this a sharp boundary. Usually it is a very diffuse, somewhat ill-defined region of interaction that has become... 

In power circuits or power devices, heat must be removed by convection by blowing air across the part, by conduction through several solid materials and interfaces to a heat sink or heat exchanger, or by a combination of conduction and convection. If heat transfer depends solely on conduction, the adhesive used for attachment is often the limiting factor providing the... 

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