Poly vinylidene chloride plastic

Cryovac W. R. Grace Co. s trade name for a light, shrink film, transparent packaging material based on poly-vinylidene chloride plastic. It is used especially for meats and other perishables. 

Saran PVC and poly(vinylidene chloride) copolymer Dow Plastics... 

Abbreviations for plastics ABS, acrylonitrile-butadiene-styrene CPVC, chlorinated poly vinyl chloride ECTFE, ethylene-chlorotrifluoroethylene ETFE, ethylene-tetrafluoroethylene PB, polybutylene PE, polyethylene PEEK, poly ether ether ketone PFA, perfluoroalkoxy copolymer POP, poly phenylene oxide PP, polypropylene PVC, polyvinyl chloride PVDC, poly vinylidene chloride PVDF, poly vinylidene fluoride. 

Internal plasticizers are synthesized by copolymerization of suitable monomers. Polymeric non-extractable plasticizers, mostly copolymers having substantially lower glass transition temperatures due to the presence of plasticizing ( soft ) segments such as poly(ethylene-co-vinyl acetate) with approximately 45 % vinylacetate content, ethylene-vinyl acetate-carbon monooxide terpolymer, or chlorinated PE, are available for rather special applications in medicinal articles (Meier, 1990). In this case, the performance of the internally plasticized polymers is the principal advantage. However, copolymerization may account for worse mechanical properties. A combination with external plasticizers may provide an optimal balance of properties. For example, food contact products made from poly(vinylidene chloride) should have at most a citrate or sebacate ester based plasticizers content of 5 % and at most 10 % polymeric plasticizers. 

A possible way to lower the cost of fibers and films of regenerated cellulose would be to run cellulose through a twin-screw ultrasonic extruder with a minimum of the solvent and passing the exudate through a stream of hot air to recover the solvent for reuse. This stronger cellophane could be used in place of many plastic films used today. The high moisture vapor transmission of cellophane is reduced by a coating of nitrocellulose or poly(vinylidene chloride), which also makes the film heat-sealable.79 Cel-... 

The flammability of plastics can be a useful tool in their identification, but the additives present have an influence on their ability to bum. A clear test to indicate the presence of chlorine, mainly found in PVC and poly(vinylidene chloride) is the Beilstein test. A clean, copper wire 30-40 cm long, with a cork or other heat-insulating material at one end as a handle, is heated with a Bunsen burner to clean it of residual impurities, heating it until the flame is colourless. The hot, cleaned wire is placed in contact with the plastic to be analysed so that a small piece is melted onto it. The wire is returned to the flame and the colour noted a green or blue-green flame denotes the presence of chlorine while other colours suggest the plastic to be other than PVC or poly(vinylidene chloride). 

Plasticizers today are used in commercially important amounts in about 35 different polymers with poly(vinyl chloride) (PVC) taking the largest share. Beyond the starting point in cellulosics, plasticizers have become highly important in poly(vinyl butyral), acrylic polymers (especially for surface coatings) and poly(vinyl acetate) (coatings and adhesives) and even in thermosets such as epoxies. Plasticizers are also used in crystalline polymers such as nylon, polypropylene, and poly(vinylidene chloride). Traditionally, extenders for rubber and synthetic elastomers were considered outside the field of plasticizers yet many such... 

Pyrolysis has been used to examine the types of air pollutants that might be generated from various types of waste plastic materials during incineration or thermal decomposition in landfills. One such study " used GC and GC/MS to examine the products that were formed when two kinds of widely used plastic wrapping film (made of poly(vinylidene chloride)) were pyrolyzed. 

Poly(vinylidene chloride) (PVDC). The homopolymer is intractable in the conventional plastics processing techniques. For this reason, copolymers of vinylydene chloride with vinyl chloride or terpolymers with vinyl chloride and acrylonitrile are used. Due to its exceptionally low vapour, gas, and aroma permeability, PVDC films are used for packaging and for the barrier layer in composite films. Paper varnished by PVDC is a widespread packaging material. Trade names Diofan (FRG), Ixan (B), Saran (USA). 

Poly(vinyl chloride) is one of the plastics that are produced in the largest quantities, whereas poly(vinylidene chloride) is produced in smaller quantities. Neither trichloroethylene nor tetrachloroethylene are homopolym-erizable, since the tendency toward transfer reactions increases with increasing... 

Vinyl chloride/vinylidene chloride monomers can be polymerized by emulsion pol3rmerization. Poly(vinyl chloride) (E-PVC) product is mostly applied as the dried form. It is spray-dried and milled to form fine powders ("crumbs") which is mixed with plasticizer to form a plastisol, i.e., dispersion of pol) vinyl chloride) particles in liquid organic media. The plastisol is poured into molds to make rubber doUs, shower curtains, embossed wall coverings and many of other common objects. In packing materials, especially for food packaging, the films of poly(vinylidene chloride) latexes are used, which are highly impermeable for both, oxygen and water vapor. 

Plasticizer studies were conducted in order to improve the foamability of the other monomeric constituents of the VDC-based copolymers. Table 4.5.2 shows the classes and formulations of the Scientific Polymer Products plasticizers used in this study. Also, water and V-methyl-2-pyrolidinone (NMP) were considered in the plasticizer studies. Studies of P(VDC-AN), poly(vinylidene chloride-co-vinyl chloride) (PVDC-VC), and poly(vinylidene chloride-co-acrylontirile-co methyl methacry-... 

GRP Glass reinforced plastic PVDC Poly(vinylidene chloride) CSM Chlorosulfonated polyethylene ABS Acrylonitrile butadiene styrene PUR Polyurethane PIR Polyisocyanurate UF Urea formaldehyde ... 

PA), polyCethylene terephthalate) (PET), ethylene vinyl alcohol (EVOH), and poly(vinylidene chloride) (PVDC). See Polyamides, plastics Polyesters, thermoplastic Vinyl Acetate Polymers Vinyl Alcohol Polymers Vinylidene Chloride Polymers (PVDC). See also Films and Sheeting. 

There are presently about 100 different plasticizers produced worldwide, although only about 50 of these are classified as commercially important. Of these 50 products, just 7 plasticizers comprise more than 80% of the global plasticizer market. Approximately 90% of all plasticizers are used in the production of plasticized or flexible PVC materials. For this reason, the majority of the information discussed in this chapter will focus on PVC plasticizers. Other polymer systems that use small amounts of plasticizers include poly (vinyl butyral) or PVB, acrylic polymers, poly(vinylidene chloride), nylon, polyolefins, polyurethanes, and certain fluoroplastics. The estimated worldwide production of plasticizers in 2014 was about 14 billion pounds [6] with the majority of the plasticizer consumption taking place in Asia Pacific, predominately China. About 75% of this volume is phthalate ester plasticizers. 

Oriented, heat shrinkable, poly(vinylidene chloride) (PVDC) films are widely used for packaging purposes, particularly for packaging food. However, vinylidene chloride copolymers need to be plasticized so that they can be extruded and stretched into oriented films at commercial rates. The greater the proportion of plasticizer, the lower the viscosity and the easier the polymer is to extrude and orient, as well as better the abuse resistance of the final product. 

Practice Problem A Saran Wrap, the original plastic fihn, is poly vinylidene chloride, which is formed by the addition polymerization of vinylidene chloride, H2C=CCl2. Draw the structure of polyvinylidene chloride, showing at least two repeating units, and write its general stmeture. 

Thus in an elementary fashion and if we consider the three broad materials categories of insulators, semiconductors and conductors (such as metals), CPs differ from typical everyday organic polymers such as poly (ethylene), poly(vinylidene chloride) ("Saran" wrap), polyesters (used in textiles) and other everyday plastics, which are generally highly insulating, in that tlieir unique 7r-electron properties impart electrical conductivity at room temperature, and many other derivative and interesting properties discussed at length in this book, on oxidation or reduction. 

Vinylidene Chloride Copolymer Latex. Vinyhdene chloride polymers are often made in emulsion, but usuaUy are isolated, dried, and used as conventional resins. Stable latices have been prepared and can be used direcdy for coatings (171—176). The principal apphcations for these materials are as barrier coatings on paper products and, more recently, on plastic films. The heat-seal characteristics of VDC copolymer coatings are equaUy valuable in many apphcations. They are also used as binders for paints and nonwoven fabrics (177). The use of special VDC copolymer latices for barrier laminating adhesives is growing, and the use of vinyhdene chloride copolymers in flame-resistant carpet backing is weU known (178—181). VDC latices can also be used to coat poly(ethylene terephthalate) (PET) bottles to retain carbon dioxide (182). 

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