Polymers, acrylate-based solution

The ratio of monomer to initiator ranges from 1 1 to 10 1, and preferentially is set to 9 1 [126]. By setting initiator concentration, initiator type, residence time and temperature, the polymer molecular weight, conversion and solution viscosity are determined. The monomer is, e.g. acrylate-based with or without styrene. The pressure is regulated to be 2 x 10 -5 x 10 Pa in order to avoid solvent and monomer boiling. 

The exchange reactions between salts of polymer adds (bases) and weak polybases (polyadds) in aqueous solutions are accompanied by considerable pH changes and also by the appearance of turbidity, particularly if the components are mixed in equivalent quantities. The copredpitation of polymeric adds and polybases was described first by Fuoss and Sadek This behavior of the mixture of two oppositely charged polyelectrolytes can be explained by the formation of a polyelectrolyte complex, this reaction being accompanied by elimination of a low-molecular weight acid or base. Thus, the exchange reaction between poly(acrylic add) and pdly(4-vinyl-ethylpyridinium bromide) was shown by potentiometry and turbidimetry to result in the precipitation of an insoluble macromolecular product, i.e. the ionic comj ex, and... 

Ethyl acrylate monomer is used to make acrylic resins as well as emulsion (water-based) and solution (solvent-based) polymers. Water-based ethyl acrylate... 

Proprietary compatibilizers-cwm-impact modifiers offer a more economic solution and are widely used. These materials are formulated for specific types of polymer mixtures, viz. Blendex — polybutadiene-type compatibilizer for styren-ics, PVC, TPU, PET, EXL — an acrylic-based additive for PEST, Fusabond — maleated-PO compatibilizer for PO/PET blends, Vector — is SBS-type block copolymers with stabilizers, designed for PO/PS commingled mixtures, etc. 

As stated above, conventional synthetic fibres may be rendered inherently flame retardant during production by either incorporation of a flame retardant additive in the polymer melt or solution prior to extrusion or by copolymeric modification before, during, or immediately after processing into filaments or staple fibres. Major problems of compatibility, especially at the high tanperatures used to extrude melt-extruded fibres like polyamide, polyester, and polypropylene and in reactive polymer solutions such as viscose dope and acrylic solutions, have ensured that only a few such fibres are commercially available. A major problem in developing successful inherently flame retardant fibres based on conventional fibre chemistries is that any modification, if present at a concentration much above 10wt% (whether as additive or comonomer), may seriously reduce tensile properties as well as the other desirable textile properties of dyeability, lustre and appearance, and handle, to mention but a few. 

For example, polyamides are typically applied as one part hot melts but are also available in alcohol base solution. Blending of polyamides with other polymers is frequently used to obtain tack and other required properties. For example, blending of amorphous polypropylene enhances peel adhesion to acrylic and canvas, and blending of phenolic resin produces high peel adhesion to plasticized polyvinyl chloride (PVC), porous materials, and metals. 

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