Polyethylene/copolyamide

The adhesive coating materials, applied to the base cloth to form the fusible interlining, are thermoplastic materials, which melt and flow in the fusing press and so form the bond between interlining and face fabric. The materials most commonly used as adhesives have already been described (under Hot melt adhesives), that is polyethylene, copolyamide, copolyester, plasticized PVC, cellulose acetate and polyvinyl acetate. 

We report here that polyethylene adipate (PEA) and polycaprolactone (PCL) were degraded by Penicillium spp., and aliphatic and alicyclic polyesters,ester type polyurethanes, copolyesters composed of aliphatic and aromatic polyester (CPE) and copolyamide-esters (CPAE) were hydrolyzed by several lipases and an esterase. Concerning these water-insoluble condensation polymers, we noted that the melting points (Tm) had a effect on biodegradability. 

In the copolyamides under consideration, the dipoles that are responsible for the dielectric relaxations are associated with the C = 0 groups of the amide functions. Due to the quasi-conjugated character of the CO - NH bond, the amide group takes on a rigid plane conformation in such a way that the dielectric relaxations of copolyamides should correspond to motional modes that involve amide groups and not only the carbonyls, in contrast to what happens with the ester groups encountered in polyethylene fere-phthalalc (Sect. 4.1.2). 

Materials. High density polyethylene (HDPE) having different molecular weights, and specific gravity of 0.951 (Marlex 5202, HXM 50100, made by Phillips 66 Co), were used for extrusion applications. Polyamides used were a semicrystalline copolyamide of adipic acid, hexamethylene diamine and caprolactam, and a copolyamide containing isophthalic acid as well. An anhydride modified polyethylene (3-5) as an interlaminar adhesive/compatibilizer was also used. The combinations are generally included in "Selar" barrier materials supplied by E. I. du Pont de Nemours Co. 

Long-Term Permeability in Polyethylene-Nylon Laminar Walled Containers. Polyolefin containers often are subject to loss of properties with aging. These result from plasticization, crystallization, and stress cracking. Figure 8 shows the permeability properties of 66/6 copolyamide based "laminar" blends. The permeability performance was found to be unchanged during over 5 years of storage in the two separate samples shown here. 

Blends of polyethylene, PE, with 0.1-50 wt% of copolyamides (e.g., LDPE with 5 wt% PE-PA-6 copolymer) showed higher gloss, transparency, and elasticity lower stress corrosion and reduced pmneability... 

The Hot melt adhesives suitable for textile use are copolyamides, copolyesters, Polyurethanes, acrylics, polyethylenes, polypropylene, ethylene copolymers (mainly with vinyl... 

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