Plastics. Also polyacrylates

Strong graphite fibers are made by pyrolysis, at 1500°C or above, of oriented organic polymer fibers (e.g., those of polyacrylonitrile, polyacrylate esters, or cellulose). When incorporated into plastics the reinforced materials are light and very strong. Other forms of graphite such as foams, foils, or whiskers can also be made. 

The UV-curing polyacrylates are particularly variable in terms of flexibility, viscosity adjustment (microdosing in the pg range), flow behavior (thixotropy), and adhesion. Flexibility is particularly important in hard-soft combinations such as plastic-metal and glass-plastic in order to compensate for expansion due to temperature variations. UV-curing adhesives are also used for cladding applications in composites. 

Several SP materials have been used for the extraction of FRs from aqueous samples, plasma and milk (Table 31.7). Similar materials have been used for all FRs. Typical SP materials include Ci8 and Cg bonded to porous silica, highly cross-linked poly(styrene divinylbenzene) (PS-DVB), and graphitized carbon black (GCB). It is also possible to use XAD-2 resin for extraction of various FRs, pesticides, and plastic additives from large volumes of water (100 1). The analytes can then be either eluted from the resin by acetone hexane mixture, or Soxhlet extracted with acetone and hexane. For a specific determination of diphenyl phosphate in water and urine, molecularly imprinted polymers have been used in the solid phase extraction. The imprinted polymer was prepared using 2-vinylpyridine as the functional monomer, ethylene glycol dimethacrylate as the cross linker, and a structural analog of the analyte as the template molecule. Elution was done with methanol triethylamine as solvent. Also solid phase microextraction (SPME) has been applied in the analysis of PBDEs in water samples. The extraction has been done from a headspace of a heated water sample (100°C) using polydimethylsiloxane (PDMS) or polyacryl (PA) as the fiber material. ... 

Saturated halogenated phosphoric esters can be admixed to polyacrylates as additive flame-retardants in a proportion of 30 to 40 per cent, or 12 to 15 per cent when chlorinated (such as tris(chloroethyl) or bis(chloroethyl) phosphates) or brominated (as with tris(bromoethyl) phosphate) agents are used. These additives also act as plasticizers. 

The effects of phase inversion may also be noted with this system. Figure 7.3 illustrates the elongation of these materials. If the morphological analysis of Figure 6.7 is correct, the drop off in elongations at about 80% polyacrylate may be due to the loss of phase continuity of the elastomer. This explanation is not completely satisfying, however, because polyacrylate, the plastic portion, is continuous over most of the composition range. Alternately, the low Tg of poly aery late may have an... 

Amino acid chromatograms have been preserved by impregnation with collodion to which a definite amount of glycerol had been added [42, 66]. Chromatograms have also been pasted over with self-adhesive plastic film and the layer subsequently peeled off the plate [354]. Spraying with polymer dispersions (polyacrylates, polyvinylidene chloride or polyvinyl propionate) is usually more suitable [402]. Such aerosols are commercially available (Firms 88, 153). Mention may be made also of impregnation of layers by immersion in solutions of polymers although this has a restricted application (Firm 60). 

Aqueous emulsions of polymeric compounds, e.g., homopolymers of vinyl acetate and vinyl propionate, vinyl acetate copoljmiers with ethylene or maleic esters polyacrylic esters, styrene copolymers. Uses paper, wood, also bonding to plastics. 

Solutions of natural and synthetic rubber, polyurethane rubber, ethylene-vinyl acetate copolymers, polyacrylates, and other polymers with additions of resins and plasticizers are also used. These polymers can be used in solvents or as dispersions in water. 

Lamination of Paper and Board. Adhesives based on starch, dextrin, glutin and poly(vinyl alcohol), and also emulsion adhesives, mainly polyfvinyl acetate), are used for the lamination of paper and board. Only when high initial tack and a lay-flat effect are required are hot glues based on glutin still in use. Starch-based adhesives modified with silicate, casein-stabilized copolymer dispersions, and rubber latices are used in the lamination of paper to aluminum foils. Modified polyacrylate solutions and reactive polyurethane adhesives are used mainly for paper-to-plastic lamination. 

The strength of a fibre can be increased by drawing, this process being discussed in Section 2.4.4 and illustrated in Fig. 2.12. Common synthetic polymers used to produce fibres are generally polyamides, polyesters or polyacrylics. The class of nylons are the most familiar polyamides. For example, the structure of nylon-6,6 (here the numerals refer to the numbers of carbon atoms between successive amide groups in the repeating unit) is shown in Table 2.1. An example of a polyester is poly(ethylene terephthalate) (PET) (Table 2.1), known commercially in fabrics as tery-lene or dacron (this polymer is also used in PET plastic drink bottles). A well-known polyacrylic used to make fibres is poly(acrylonitrile) (Table 2.1). 

Uniplex 225 is a Highly effective plasticizer for polyamide and polyurethane polymers with excellent anti-static properties. Also suggested for use in polyacrylic and cellulose ester. Exhibits excellent resistance to extraction by water and dry cleaning solvents. 

A peroxide curable grade, HyTemp PV-04, is available liom Zeon Chemicals for 0-rings, seals, gaskets as well as binders, adhesives, caulks, and plastic modification. This grade offers good compression set without the need for a post-cure, but is sensitive to exact curative levels [15]. NOK also has a polyacrylate that may be cured with peroxides, but information on it is not readily available. 

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