PVDC Poly Vinylidene Chloride

Fig. 10. Adsorption ( , O)"desorption (A, A) isotherms of water vapor on poly(vinylidene chloride) (PVDC) carbon before (filled symbols) and after...

Poly(vinyl chloride) (PVC) Poly(vinylidene chloride) (PVDC) Poly (vinyl alcohol) (PVOH) Poly(vinyl acetal)... 

Heat stabilizers protect polymers from the chemical degrading effects of heat or uv irradiation. These additives include a wide variety of chemical substances, ranging from purely organic chemicals to metallic soaps to complex organometallic compounds. By far the most common polymer requiring the use of heat stabilizers is poly(vinyl chloride) (PVC). However, copolymers of PVC, chlorinated poly(vinyl chloride) (CPVC), poly(vinylidene chloride) (PVDC), and chlorinated polyethylene (CPE), also benefit from this technology. Without the use of heat stabilizers, PVC could not be the widely used polymer that it is, with worldwide production of nearly 16 million metric tons in 1991 alone (see VlNYL polymers). 

The 1,1-disubstitution of chlorine atoms causes steric interactions in the polymer, as is evident from the heat of polymerization (see Table 1) (24). When corrected for the heat of fusion, it is significantly less than the theoretical value of —83.7 kJ/mol (—20 kcal/mol) for the process of converting a double bond to two single bonds. The steric strain apparendy is not important in the addition step, because VDC polymerizes easily. Nor is it sufficient to favor depolymerization the estimated ceiling temperature for poly(vinylidene chloride) (PVDC) is about 400°C. 

In the present section, general comparisons will be presented between these two theories. Both theories will be utilized in a correlative mode. The parameters for barrier polymers will be defined for idealized completely amorphous poly(vinylidene chloride) (PVDC) and a VDC/VC copolymer. It will be shown that physically significant qualitatitive differences exist between the results calculated by the two theories. 

Radiation-induced dehydrochlorination of polyvinyl chloride (PVC) and poly(vinylidene chloride (PVDC) and concomitant doping of polyaniline (PANI)-base with released HCL (From Guven, O., Radiation-induced conductivity control in polyaniline blends/composites. Radiation Physics and Chemistry 2007,76,1302-1307. With permission.)... 

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(vinylidene chloride) (PVDC) -35 Saran wrap... 

Narrow and relatively narrow molecular weight distribution (MWD) homopolymers comprise an obvious group of products that can be produced from the FRRPP process. These materials would be used mainly for R D purposes. PS and PMAA homopolymers would be good examples of relatively narrow MWD homopolymers that can be produced in large scale through the FRRPP process. Recently, poly(vinylidene chloride) (PVDC) has been produced through the FRRPP process, including various related copolymers. 

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. 

Poly(vinylidene chloride). The carbon-chlorine dipole in poly(vinylidene chloride) (PVDC) has been oriented to produce a low level of piezoelectricity. The piezoelectric and pyroelectric activities generated in PVDC are stable and reproducible. PVDC has been used as a basis for understanding and studying piezoelectricity in amorphous polymers (39). The piezoelectric coefficients dsi of PVDC are reportedly in the range of 0.5-1.3 pC/N. This response was improved by simultaneous stretching and corona poling of film (44). The enhanced piezoelectric coefficient dsi ranged from 1.5-5.0 pC/N (see Vinylidene Chloride Polymers (PVDC)). 

Carbonization of polymers, such as poly(vinylidene chloride) (PVDC) (Walker et al., 1966 Dacey and Thomas, 1954 Dubinin et al., 1964 Lamond et al, 1965) Saran (90/10 mixture of vinylidene chloride and vinyl chloride) and cellulose, sugar, and coconut shell. 

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