Bonding thermoplastics

EP4802-75. [Lord] Two-component adhesive for bonding thermoplastic polyolefin elastomers to textiles, leadier, cured rubber. 

HMS have been chemically modified using (3-aminopropyl)triethoxysilane (APTES). A solution (30 ml) of HMS (0.1 g) and APTES (2 ml) was prepared in toluene. In fact, APTES, an aminosilane, can be used in the silanisation process to functionalise the HMS surfaces with alkoxysilane molecules. APTES can also be used to covalently bond thermoplastics to polydimethylsiloxane (PDMS). APTES-functionalised HMS surfaces have been shown to be non-toxic to embryonic rat cardiomyocytes in vitro. In this study, the resulting magnetite/silicon particles were washed with ethanol and then dried under vacuum at 60 C for 24 h [57]. The obtained amine-functionalised HMS (HMS-NHi) were dispersed by ultrasound in toluene (30 ml). Another modification involved D,L-lactide (0.4 g) and PEG (0.1 g), which were placed into a three-neck round-bottom flask containing a magnetic stirrer. The catalyst, Sn(Oct)2, was added to the flask at a concentration of 0.1% of the solution the flask was put into an oil bath to react for 24 h at 110 C in nitrogen under ambient conditions [58]. 

Products classified as first generation are still on the market and are sold primarily for bonding thermoplastics. They provide excellent gap filling characteristics, rapid cure and adhesion, and are generally stronger than the substrates themselves. 

Fig. 4 Hydrogen-bonded thermoplastic elastomer based on self-complementary interactions of ureido-pyrimidinone (UPy). (a) Poly(ethylene-co-butylene) with OH end groups, (b) Poly(ethyl-ene-co-butylene) functionalized with UPy. (c, d) Lateral intraactions through tt—tt stacking of UPy and hydrogen bonding of urethane linkers, (e) AFM image of nanofibers formed through these lateral interactions. Reprinted with permission friun [90-92]. Copyright 2000, 2006, 2008 Wiley-VCH Verlag GmbH, Wiley Periodieals, Ine., and American Chemical Society...

Table 5.5 Strength Characteristics of Thermo-Bond Thermoplastic Adhesive Film Used to Bond to Etched Aluminum ...

Solvents, or solvents containing small amounts of hodying resin, are used for bonding thermoplastic resins and film adhesives. An example is toluol, which can he used to soften and dissolve polystyrene molded articles to allow joining the softened pieces. Ketones can be used to bond PVC films in a similar manner. A small amount of resin can be used to thicken the solvent so that a sufficient amount would stay in place to dissolve the substrate. It should be noted, however, that solvent welding of molded plastics can cause stress cracking and weakening of the structure as the parts age. ... 

A method of bonding thermoplastic articles of like materials to each other by using a solvent capable of softening the surfaces to be brmded. Thermoplastic materials that can be bonded by this method are ABS, PA, PC, PS, acrylics, ceUulosics, and vinyls. 

Benatar A and Gutowski T G (1986) Methods for fusion bonding thermoplastic composites,... 

For NCA bonding, thermoplastic melt adhesives are used normally because of their easy handling. A commonly used adhesive includes the class of thermoplastic polyurethanes. Also, conductive metal foils can be utilized when attempting to bond larger surfaces in shorter times. To achieve a reliable electrical contact, pressure is applied to... 

Solvents used for bonding can be pure solvents, a solvent slurry, or a solvent mixture. Pure solvents have only one component (n-hexane, water, acetic acid, etc.) and are used to bond thermoplastics when mating surfaces are in good contact and no gap filling is required. A solvent slurry or solvent dope, a solution of a solvent and dissolved thermoplastic pellets, is more viscous than a pure solvent and is useful when gap filling is required. Pellets should be the same material as the thermoplastic parts slurries can contain up to 25% solids. Slurries with high solids contents are very viscous and can sometimes be used to repair surface imperfections on the parts.f ]... 

Electromagnetic materials are micron-sized ferromagnetic powders of different types, particle sizes, and concentrations. They can be metallic (iron, stainless steel) or nonmetallic, ceramic (ferrite) material. For bonding thermoplastics, they are enclosed in a thermoplastic matrix that is compatible with the plastics being joined.f ]f ]f ]... 

For bonding thermoplastic parts made from the same material, the matrix is generally the same material as in the part and can be matched on melt flow. For dissimilar materials, a blend of the two thermoplastics is used. Type and cross-section of the EMA material (ferromagnetic filler -i- thermoplastic matrix) are dependent on the size and shape of the parts to be welded and on the position of the work coils. EMA material is supplied in many different forms (Fig. 14.33) strands and extruded profiles (continuous reels and precut), tapes and strips up to 30 cm wide, stampings and in-j ection-molded parts. 

Manufecturers Comments 100% solids. Dieleciric adhesive. Flexl)le, high st ngth for bonding thermoplastics. 

VAR 5831 Extremely flexible adhesive with outstanding bonds to metal (preheated) and thermoplastics. Recommended for bonding thermoplastic films. PET (Mylar), (Tedlar), polyurethane, vinyl, moderate temperature service level. 149 218 250 Slow -10°C 150°F... 

Some durability evaluations use a combination of these elements of accelerated ageing. For example, an indication of the durability of adhesives used for bonding thermoplastic pressure pipe systems is given in EN 14814 2007, Adhesives for thermoplastic piping systems for fluids underpressure. Specifications, which references the test method given in ISO 9311-3, where test... 

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