Vinyl polymers polyolefins

Most commonly used separator materials for alkaline Zn/Mn02 batteries are nonwoven polymers, such as cellulose, vinyl polymers, polyolefin, and others. The separator materials must be chemically stable in concentrated KOH solutions and electrochemically stable under both oxidizing and reducing conditions in the cell. In addition to its good electronic insulation, physical strength, and porous structure, good wettability to concentrated KOH solutions is especially crucial to provide a good ionic pathway for the battery operation. 

In the case of poly(vinyl chloride) plastics, the FWA is mixed dry with the PVC powder before processing or dissolved in the plasticising agent (see Vinyl polymers). Polystyrene, acrylonitrile—butadiene—styrene (ABS), and polyolefin granulates are powdered with FWA prior to extmsion (2,78) (see... 

A large number of hindered phenoHc antioxidants are based on the Michael addition of 2,6-di-/ f2 -butylphenol and methyl acrylate under basic catalysis to yield the hydrocinnamate which is a basic building block used in the production of octadecyl 3-(3,5-di-/ f2 butyl-4-hydroxyphenyl)propionate, [2082-79-3], tetrakis(methylene-3(3,5-di-/ f2 butyl-4-hydroxylphenyl)propionate)methane [6683-19-8], and many others (63,64). These hindered phenolic antioxidants are the most widely used primary stabilizers in the world and are used in polyolefins, synthetic and natural mbber, styrenics, vinyl polymers, and engineering resins. 2,6-Di-/ f2 -butylphenol is converted to a methylene isocyanate which is trimerized to a triazine derivative... 

Incorporation of carboxyl groups in vinyl polymers (J) and polyolefins (1, 7) improves the adhesion of these polymers to various materials. However, many of these carboxylated polymers, particularly the carboxylated polyolefins, have limited solubility in volatile, lacquer-type solvents such as butyl acetate or methyl ethyl ketone and thus are limited in their ability to improve the adhesion of coatings applied from solvents. Carboxylated polyesters that are soluble in these solvents can be prepared. We were therefore interested in determining the effects of structure and carboxyl content on the adhesion of coatings of various classes of polymers blended with carboxylated polyesters. 

Homogeneous Vinyl polymers Polyethers Polyes t ers, Polyolefins... 

T his paper presents a polymerization reaction, as yet unreported in the literature, wherein block polymerization of a free radical type can be caused to take place onto an actively growing chain which had proceeded by an anionic mechanism. Specifically, a Ziegler type of polymerization, such as that of propylene or ethylene, can be interrupted by adding vinylic monomers and an organic peroxide, and a vinyl polymer grown on the end of the polyolefin. For simplicity we will refer to these types as anionic free radical (AFR) polymerizations. 

Examples polyolefins, polydienes, vinyl polymers, acrylic polymers... 

The majority of packaging plastic materials consists of polyolefins and vinyl polymers, namely polyethylene (PE), polypropylene (PP), polystyrene (PS) and poly(vinyl chloride) (PVC). Obviously, these polymers have many other applications not only as packaging materials. Chemically they are all composed of saturated hydrocarbon chains of macro-molecular size their typical thermal decomposition pathway is free radical one initiated by the homolytic scission of a backbone carbon-carbon bond. In spite of the basic similarity of the initial cleavage, the decomposition of the hydrocarbon macroradicals is strongly influenced by fhe nafure of the side groups of the main chain. 

Recently the pyrolysis of polymer mixtures has become a focus of interest due to the increasing role of plastics recycling. Many researchers have investigated the thermal decomposition of various polymers in the presence of PVC. Kniimann and Bockhom [25] have studied the decomposition of common polymers and concluded that a separation of plastic mixtures by temperature-controlled pyrolysis in recycling processes is possible. Czegfny et al. [31] observed that the dehydrochlorination of PVC is promoted by the presence of polyamides and polyacrylonitrile however, other vinyl polymers or polyolefins have no effect on the dehydrochlorination. PVC generally affects the decomposition of other polymers due to the catalytic effect of HCI released. Even a few per cent PVC has an effect on the decomposition of polyethylene (PE) [32], HCI appears to promote the initial chain scission of PE. Day et al. [33] reported that PVC can influence the extent of degradation and the pyrolysis product distribution of plastics used in the... 

What are the trends in the polymeric foam industry The production of foamed plastics on the basis of high polymers will continue to expand mainly utilizing common raw materials (polystyrene, poly(vinyl chloride), polyolefins and synthetic resins). Apart from that, one should expect a strong increase in the commercial pro-... 

A helical structure for vinyl polymers with an excess helicity in solution was realized for isotactic poly(3-methyl-1-pentene) by Pino in I960.12 Although the chiral side groups affect the helical conformation in the polyolefin, the single-handed helix of poly-... 

Helical conformations were also proposed for the isotactic copolymer derived from (/T)-3,7-d imethyl-1 -octene and styrene.48,49 The copolymer showed intense CD bands based on the styrene units incorporated into the polymer chain. The CD intensity was much larger than that of a model compound of an adduct of the chiral olefin and styrene. The helical structure of polyolefins has also been supported by force field calculations.50 The relationship of these considerations to isotactic vinyl polymers and more recent studies have recently been reviewed.41... 

Homogeneous Solution bulk Vinyl polymers (styrene, MMA, LDPE) Polyethers (ethylene oxide), SBR Polyolefins Polyesters, polyamides... 

Heterogeneous Emulsion dispersion Suspension Precipitation Solid catalyzed Vinyl polymers (styrene, MMA, PVC) Vinyl polymers (styrene, MMA, PVC) Vinyl polymers (PVC, PAN, PVDC) Polyacetals, vinyls Polyolefins, syndiotactic polystyrene Polyamides, solid state polymerization... 

NMR chemical shift prediction by quantum chemical calculation and the 7-gauche effect method has become a useful approach for stereochemical assignment of vinyl polymers. Recently C NMR assignments based on 7-effect and the rotational isomeric model were demonstrated successfully for a series of polyolefins, poly(l-pentene) to poly(l-octene).188... 

Polymers polyolefins, vinyls, polystyrene, polyester, melamine, and terephthalic acid... 

Nonolefinic thermoplastic polymers that in principle may be blended with polyolefins include polyamides (nylons) such as polyamide 6, polyamide 66, polyphenylene sulfide (PPS), polyphenylene ether (PPF), and polyphenylene oxide (PPO) polyesters such as polyethylene terephthalate (PET), polybutylene terephtha-late (PBT), polyethylene naphthalate (PEN), polytrimethylene terephthalate (PTT), polycarbonates, polyethers, and polyurethanes vinyl polymers such as polystyrene (PS), polyvinyl chloride (PVC), polymethylmethacrylate (PMMA), and ethylene... 

All vinyl polymers are addition polymers. To differentiate the, the homopolymers have been classified by the substituents attached to one carbon atom of the double bone. If the substituent is hydrogen, alkyl or aryl, the homopolymers are listed under polyolefins. Olefin homopolymers with other substituents are described under polyvinyl compounds, except where the substituent is a nitrile, a carboxylic acid, or a carboxylic acid ester or amide. The monomers in the latter cases being derivatives of acrylic acid, the derived polymers are listed under acrylics. Under olefin copolymers are listed products which are produced by copolymerization of two or more monomers. 

The Cromophtal product assortment from Ciba Spezialitatenchemie (Switzerland) is particularly low-warping in polyolefins and vinyl polymers. 

Motor vehicles, fire scene debris, and household utensils from crime scenes are materials that may contain plastics. Their identification and comparison are often necessary to further the criminal investigation. A wide range of thermoplastic and thermosetting plastics may be encountered as crime scene evidence. These include polyolefines, polyacrylates, polyamides, polyesters, epoxies, and vinyl polymers. Pyrograms of some of these types are shown in Figure 8.9. 

To prepare polyolefin blends, PO (e.g., EVAc, PE, PP, EPR), with vinyl polymers, 10-200 parts of vinyl monomer [e.g., (meth)acrylates, styrenics, vinyl chloride, glycidyl methacrylate, maleic anhydride, acrylonitrile, divinylbenzene] and 0.01-4.0 parts of a free radical initiator were used to impregnate 100 parts of PO particles at T = 20-130 °C. After 50-99 wt% of the monomer was absorbed, the particles were dispersed in water and the free radical polymerization initiated. Good adhesion between the components in the extruded or molded articles was achieved... 

Powder coatings are not necessarily based on epoxy resins the first powder coatings were based on thermoplastic polymers, and polyolefin, vinyl polymer and polyamide coatings are still used. While those based on epoxy resins are very prominent, there are also polyester, polyurethane and acrylic thermosetting types which we will describe here. 

Parts containing undercuts are not usually ejected directly after the mold is open. With flexible polymers, the part can be stripped off the core. For vinyls, polyruethanes, polyolefins, and elastomers, this requires an angle of 33° on molded threads, and the threads should be interrupted to give better flexing of the outer wall. Slide core molds are used for parts with internal and external undercuts such as ribs, gaps, openings. 

Most commonly used matrix materials for thermoplastic PMC in construction are polyolefinics (PE, PP), vinylic polymers (PVC, PTFE), polyamides (Nylons), polyacetals, polyphenylenes [polyphenylene sulfide (PPS)], polysulfone and poly-ether-ether-ketone (PEEK). All of these are discussed in the first part of this chapter and some of their characteristic properties are presented in Table 6.8. 

The pol3miers given in this chapter are divided into polyolefines, vinyl polymers, fiuoropolymers, polyacrylics, polyacetals, polyamides, polyesters, polysulfones, polysulfides, polyimides, polyether ketones, cellulose, polyurethanes, and thermosets. The structural units of the polymers are as follows ... 

The following tables and diagrams contain physical and physicochemical properties of common polymers, copolymers, and polymer blends. The materials are arranged according to increasing number of functional groups, i. e. polyolefines, vinyl polymers, fiuoropoly-mers, polyacrylics, polyacetals, polyamides, polyesters, and polymers with special functional groups [3.2-16]. 

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