Styrene-acrylonitrile bonding, solvent

An appropriate formalism for Mark-Houwink-Sakurada (M-H-S) equations for copolymers and higher multispecies polymers has been developed, with specific equations for copolymers and terpolymers created by addition across single double bonds in the respective monomers. These relate intrinsic viscosity to both polymer MW and composition. Experimentally determined intrinsic viscosities were obtained for poly(styrene-acrylonitrile) in three solvents, DMF, THF, and MEK, and for poly(styrene-maleic anhydride-methyl methacrylate) in MEK as a function of MW and composition, where SEC/LALLS was used for MW characterization. Results demonstrate both the validity of the generalized equations for these systems and the limitations of the specific (numerical) expressions in particular solvents. 

In this paper a generalized approach is presented to the derivation of H-H-S equations for multispecies polymers created by addition polymerization across single double bonds in the monomers. The special cases of copolymers and terpolymers are derived. This development is combined with experimental results to evaluate the numerical parameters in the equations for poly(styrene-acrylonitrile ) (SAN) in three separate solvents and for poly(styrene-maleic anhydride-methyl methacrylate) (S/HA/MM) in a single solvent. The three solvents in the case of SAN are dimethyl formamide (DMF), tetrahydrofuran (THF), and methyl ethyl ketone (MEK) and the solvent for S/HA/HH is HER. 

Hexafluoroacetone trihydrate n. A solvent cement, active at room temperatures, for bonding acetal resin articles to themselves and to other polymers such as nylon, acrylonitrile-butadiene-styrene, styrene-acrylonitrile, polyester, cellulosics, and natural or synthetic rubber. It is also a toxic irritant, so it must be handled with care. 

Acrylonitrile-Butadiene-Styrene (ABS). ABS plastics are derived from acrylonitrile, butadiene, and styrene. ABS materials have a good balance of physical properties. There are many ABS modifications and many blends of ABS with other thermoplastics that can affect adhesion properties. ABS resin can be bonded to itself and to other materials with adhesives, by solvent cementing, or by thermal welding. 

Acrylonitrile - Butadiene - Styrene (ABS) ABS is conventionally bonded with a dope cement containing 15-25% ABS resin in a blend of ketone solvents, e.g., acetone, methyl ethyl ketone, and methyl isobutyl ketone, or tetrahydrofiiran or methylene chloride (5). 

This technique allows the formation of many different types of block copolymers. Lithium metal can be used to initiate polymerizations in solvents of varying polarity. Monomers, like styrene, a-methylstyrene, methyl methacrylate, butyl methacrylate, 2-vinylpyridine, 4 vinylpyridine, acrylonitrile, or methyl acrylate, can be used. The mechanism of initiation depends upon the formation of ion radicals through reactions of lithium with the double bonds ... 

Styrenic thermoplastics include polystyrene itself, acrylonitrile-butadiene-styrene (ABS) copolymers and plastic blends such as polyphenylene oxide/styrene. Most adhesives can be used to produce strong bonds with these plastics, but primers and solvents should be tested carefully for solvent attack or cracking. 

Bodied solvent cements are usually used to bond acrylonitrile—butadiene-styrene (ABS). Adhesives recommended include epoxies, urethanes, second-generation acrylics, vinyls, nitrile-phenolics, and cyanoacrylates [24,25]. 

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