Compatibilizing agents plasticizers

Intense commercial and academic interest in block copolymers developed during the 1960s and continues today. These materials attract the attention of industry because of their potential for application as thermoplastic elastomers, tough plastics, compatibilizing agents for polymer blends, agents for surface and interface mo dification, polymer micelles, etc. Academic interest arises, primarily, from the use of these materials as model copolymer systems where effects of thermodynamic incompatibility of the two (or more) components on properties in bulk and solution can be probed. The synthesis, characterization, and properties of classical linear block copolymers (AB diblocks, ABA triblocks, and segmented (AB)n systems) have been well documented in a number of books and reviews [1-7] and will not be discussed herein except for the sake of comparison. 

Silanes have found a rather wide application as coupling agents and compatibilizers in plastics filled with minerals [9,10], A general formula for the silanes is as follows ... 

It is unusual to find different plastics that mix at the molecular level. A blend of two plastics rarely produces a system with a single homogeneous phase and that is thermodynamically stable. A compatible system is considered to be a useful multicomponent plastic blend that has desirable properties. Some incompatible plastic blends may be made useful by the presence of an additive, frequently termed a compati-bilizer or compatibilizing agent. 

Compatibilizers are frequently materials such as block or graft copolymers. A specific example would be a copolymer comprising two blocks where each is compatible with one component of the blend (in a blend of two plastics) and incompatible with the other. An A-x-B block copolymer, where A and B are long sequences of monomer that are identical to the corresponding A and B polymers forming the blend, and X is a bond between the blocks, is one of the simplest forms of compatibilizer. A functionalized polymer where the main polymer is compatible in one phase and the functionality is compatible in the other phase would be another example of a compatibilizing agent. One example of such a material would be maleic anhydride functionalized polypropylene (PP-MA) used to compatibilize blends of PP and Nylon 66. Recent advances in the production of PP-MA have seen an increase in the impact resistance of... 

The literature is abundant in data on the photochemical behavior of thermosetting matrices based composites. Most of the reported data focused on two main issues (a) the UV-cured composites and nanocomposites and (b) the photochemical degradation of these materials upon UV exposure. In the first case, the UV radiation is employed in the synthesis of various materials starting from thermoset precursors included in complex formulations that may also contain— besides fillers, whether fibers or particles— initiators, plasticizers, compatibilizing agents, UV absorbers. 

Internal ester and amide lubricants are often added early in the batch, particularly with blends, to function as compatibilizing agents. Powder stabilizers can be added with the resin if they are nonlubricating otherwise they should typically be added with external lubricants. Two-stage addition of plasticizer is again common with high loadings. 

This chapter reports successful initial efforts to bond wood in the presence of hydrophobic plastic material [polystyrene (PS)] using well-defined and tailored cellulose-polystyrene graft polymers as compatibilizers or interfacial agents. The synthesis of these tailored cellulose graft polymers is also presented. 

Encouraging results on the bonding of plastics to wood using tailor-made cellulose-polystyrene graft polymers as compatibilizers or interfacial agents may offer a new approach to the engineering of wood-plastic products with improved mechanical and physical properties for a variety of applications. It also holds the potential of opening up new markets for renewable resources in the form of woody materials. For example, polystyrene production is currently 3.9 billion... 

MAJOR PRODUCT APPLICATIONS purification agent, asbestos replacement, filler in plastics and mbber, adhesives, blend compatibilizer... 

Advancements in synthetic polymer chemistry have allowed a remarkable range of new nonlinear block copolymer architectures to be synthesized. The result is a wide variety of new materials with the capacity to form self-assembled phases in bulk and in solution. At present our synthetic capabilities exceed our understanding, both theoretical and experimental, of the properties of such macro-molecular systems. We anticipate that a better understanding of structure-property relationships for these materials will lead to impressive new polymers with applications such as structural plastics, elastomers, membranes, controlled release agents, compatibilizers, and surface active agents. From the synthetic standpoint it seems likely that recent advances in living free radical polymerization will make the syntheses of many non-linear block copolymers more commercially appealing. 

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