Miscellaneous Polymer Blends

As expected, there are some interesting blends that do not fit the classifications chosen for this chapter and will be summarized in this section. PHE/PVME blends were shown to be miscible with lest behavior observed [ 180]. Partial methylation or benzylation of the secondary hydroxyls of PHE lowered the position of the lest and thus reduced the inherent miscibihty [1140]. PHE was also shown to exhibit miscibility with poly(4-vinyl pyridine), presumably due to the hydrogen bonding potential expected from this combination [223]. The polyformal from the reaction product of tetramethyl Bisphenol S and methylene chloride was foimd to be miscible with styrene-acrylonitrile copolymers (24, 28 and 42 wt% AN) and also poly(vinyl chloride) [1141]. 

A method for fabrication of films with thousands of alternating layers produced by layer multiplying coextrusion has been described, where the individual layers can approach the thickness of the blend interphase region [1142]. This method applied to PMMA/PC blends allowed thin PMMA nanolayers ( 5 nm) positioned between thicker PC layers. For PMMA layers 12 nm, the interphase thickness was constant and equal to 12 nm. Oxygen permeability measurements 

A comprehensive review of miscible polymer blends can be found in [ 1150], listing many of the systems noted in this chapter as well as many others not specifically noted. This review is the most complete listing of miscible polymer blends existing in the literature. 

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Polymer blends of PHB and PLA have previously been analyzed with miscellaneous methods by several other groups [49-51]. In the following, the used of transmission FT-IR imaging will be demonstrated as an alternative approach towards a better understanding of the chemical and physical properties of these materials. 

Miscellaneous applications (polymer blends, modifiers with polystyrene or styrene acrylonitrile butadiene terpolymers) 15 ... 

Miscellaneous Applications of Polymer Blend Technology in Emerging... 

One of the fields of polymer science for which FT-IR imaging has proved of extraordinary importance in terms of scientific and practical aspects is the analysis of phase separation in polymer blends. Blending of different polymers is a Ifequently used technique in industrial polymer production to optimize the material projrerties. As pointed out in Chapter 5.01, the mechanical properties of PHB can be enhanced by blending with FLA. For the preparation of the optimum blend, it has to be taken into account that the miscibility of different polymers depends on their concentration, the temperature, and their stmaural characteristics. Polymer blends of PHB and PLA have previously been analyzed with miscellaneous methods by several other researchers and in what follows the application of transmission FT-IR imaging will be demonstrated as an alternative approach toward a better tmderstanding of their chemical and physical properties. 

Miscellaneous Plasticizers. Hydrocarbons and halogenated hydrocarbons belong mainly to the secondary plasticizer type. Aromatic and aliphatic hydrocarbons are used as extenders coumarone-indene resins and coal tar oils are miscible with rubber and slightly miscible with vinyl polymers. Alkylnaphtha-lenes are used as lubricants for vinylic polymers. Chlorinated hydrocarbons are used as secondary plasticizers in PVC, rubber or cellulose acetate-based blends to increase the resistance to inflammation. 

Nitrile polymers have found a varied number of applications in the adhesive area. These applications are based on the excellent elastomeric properties of the polymer coupled with its polarity which gives the material good solvent resistance and compatibility with other polar materials. The various commercially available physical forms of nitrile polymers (slab rubber, crumb rubber, liquid rubber and latex) have also increased the ease of processing of the material and broadened the application base. In an attempt to review this broad area, the applications have been subdivided into three parts. In the first section applications involving solely nitrile rubber as the base polymer as well as miscellaneous nitrile rubber blends are reviewed. Due to the large number of applications involved, nitrile rubber/pheno-lic blends have been separated into the second section. For the same reason, nitrile rubber/ epoxy blends are covered separately in the third section. 

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