Bonding polyesters

Olefin fiber is an important material for nonwovens (77). The geotextile market is stiU small, despite expectations that polypropylene is to be the principal fiber in such appHcations. Disposable nonwoven appHcations include hygienic coverstock, sanitary wipes, and medical roU goods. The two competing processes for the coverstock market are thermal-bonded carded staple and spunbond, both of which have displaced latex-bonded polyester because of improved strength, softness, and inertness. 

The use of steam is generally limited to polypropyleae and polyethylene fusion because impractical pressures are required to reach the temperature levels, eg, >200° C, required for bonding polyesters. In general, greater temperature control is required for area bonding polypropylene than for other polymers because the temperature difference between the matrix and biader fibers can be only 3°C (26). 

The fungus assimilated various polyesters. In general, assimilation of aliphatic polyesters by the fungus was better the greater the number of carbon atoms between the ester bonds. Polyesters with side chains were generally less assimilated than without side chains. The fungus also assimilated unsaturated aliphatic polyesters, but hardly assimilated alicyclic and aromatic polyesters. 

Thermosets A number of thermosets have been used as adhesives. Phenolic resins were used as adhesives by Leo Baekeland in the early 1900s. Phenolic resins are still used to bind together thin sheets of wood to make plywood. Urea resins have been used since 1930 as binders for wood chips in the manufacture of particle board. Unsaturated polyester resins are used for body repair and PUs are used to bond polyester cord to rubber in tires, and vinyl film to particle board, and to function as industrial sealants. Epoxy resins are used in the construction of automobiles and aircraft and as a component of plastic cement. 

Unsaturated polyester resins have replaced lead for auto body repair, and polyurethanes (PUs) are being used to bond polyester cord to rubber in tires, to bond vinyl film to particleboard, and as industrial sealants. Epoxy resins are used in automotive and aircraft construction and as a component of plastic cements. 

Condensed Tannins as Substitutes for Resorcinol in Bonding Polyester and Nylon Cord to Rubber... 

Specialty product for bonding polyester sewing threads. Exhibits very high adhesion to polyester imparting excellent cohesion. Dries to a slightly tacky film which improves package build and stability. 

Highly effective flame retardant for bonded polyester fiber and reclaimed fiber blends. 

The synthesis of cu-amino-substituted 18-crown-6 and [2.2.2]cryptand readily bonded with chloromethylated polystyrene cross-linked by different amounts of DVB, is described [86]. Such bonded polyesters are used as interfacial transfer catalysts promoted by anions. As in the case of analogous soluble systems, the catalytic activity of cryptands is higher than that of crown ethers and quaternary onium salts. Because of their high chemical stability, such catalysts can be regenerated without chemical decomposition. However, the impairment of mechanical properties caused by comminution of the polymer matrix remains to be solved. 

The more viscous, mastic-type cements include some of the epoxies, urethanes and sflicones. Epoxies adhere well to both thermosets and thermoplastics. But epoxies are not recommended for most polyolefin bonding. Urethane adhesives have made inroads into flexible packaging, the shoe industry, and vinyl bonding. Polyester-based polyurethanes are often preferred over polyether systems because of their higher cohesive and adhesive properties. Sflicones are especially recommended where both bonding and sealing are desired. 

The adhesives in Table 5 have many industrial applications. For example, EC-3535 B/A has been used to bond aluminum extrusions into auto roofs while EC-3532 B/A has been used to bond vinyl clad wire to printed circuit board. Urethane adhesives have also been us ed to bond polyester molded resin to the steel frame in Corvette auto bodies. 

The commercial polymers have molecular weights of up to 100,000 g/mol and ratios of primary-.secondary tertiary amino groups of 1 2 1. They are used as adhesives (e.g., bonding polyester cord to rubber), paper additives, etc. Quaternized poly(ethylene imines) form water-soluble polycations and are used as flocculants in the processing of tap water. 

Other minor uses include bonding polyester laminates to polyester or to metal, and as adhesives for optical equipment. CR-39 allyl diglycol carbonate is an example of the latter. This material, in the cured condition, exhibits improved abrasion and chemical resistance over other transparent adhesive resins and displays the good heat resistance and dimensional stability associated with thermosetting systems. These properties are retained on prolonged exposure to severe environmental conditions. CR-39, which stands for Columbia Resin 39, is an allyl resin, a special type of unsaturated polyester. ... 

Core-Bond, Polyester-based syntactic adhesives, ATC Chemical Corp. 

Bonding, polyester based Cook Composites Polycor970 Series 268... 

A special blend of polymers that produces an air-cure film which bonds polyester resins and coatings to epoxy resins and coatings. Can be spray, brush or roller applied. Also excellent for use as an air-cure coating for corrosion-resistant air-inhibited systems. 

Within this area, nonwovens find application as internal product components, such as support and cover materials for mattresses as well foam replacements. As discussed, bonded polyester wadding (used in low stress applications), thermally bonded nonwovens, and nonwovens laminated with woven or knitted fabrics to provide covers with high dimensional stability are used in the production of foam-backed mattresses for upholstery as support and cover materials. Needled waddings and paddings are incorporated into furniture as insulation and comfort layers. Fibres used for such applications include recycled natural and synthetic fibres obtained from waste clothing, bast fibres, cotton, and virgin synthetic fibres, such as PET, PP, and acrylic (Anand et al., 2007, p. 253). 

Hamed G R, Chung K H, Hemingway R W (1989) Condensed tannins as substitutes for resorcinol in bonding polyester and nylon cord to rubber. In Hemingway R, Conner A H (eds) Adhesives from renewable resources. ACS Symp Ser Washington DC 242-253... 

The rebated lap joint (Fig. 7.12c). This is an excellent variant of the simple lap joint. It can be used effectively for bonding polyester or epoxy based composite, metal (particularly sheet metal) and metal to composite. Unless gross distortion occurs and causes peel and cleavage of the joint, normal structural loads will induce compressive forces in the critical regions and premature failure will be suppressed. 

This was achieved by using a bonded polyester fiber, which proved almost impossible to tear. The strength of the polyester allowed the media to be operated at higher velocities without fear of fiber loss, which can be a limitation with the brittle glass fibers used in conventional filtration. 

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