Fluorocarbon additive

Four polymers with different surface compositions were used in this study—polystyrene (PS), poly(methyl methacrylate) (PMMA), polyacrylamide (PAM), and a poly(vinylidene chloride) (PVeC) copolymer (containing 20% polyacrylonitrile). Polystyrene has essentially a hydrocarbon surface, whereas the surfaces of poly (methyl methacrylate) and polyacrylamide contain ester and amide groups, respectively. The surface of the poly(vinylidene chloride) copolymer on the other hand will contain a relatively large number of chlorine atoms. The presence of acrylonitrile in the poly(vinylidene chloride) copolymer improved the solubility characteristics of the polymer for the purposes of this study, but did not appreciably alter, its critical surface tension of wetting. Values of y of these polymers ranged from 30 to 33 dynes per cm. for polystyrene to approximately 40 dynes per cm. for the poly(vinylidene chloride) copolymer. No attempt was made to determine e crystallinity of the polymer samples, or to correlate crystallinity with adsorption of the fluorocarbon additives. 

The incorporation of a fluorocarbon additive in PAM presented a somewhat different problem than the previous polymers, inasmuch as it required a fluorinated additive that has some solubility in water. The partially fluorinated additives, I to VII, are insoluble in water and fail to disperse in the polymer when added to aqueous solutions rather they form a separate phase and settle to the bottom of the sample dish. Additive VIII was therefore selected for use in this polymer, as Guenthner and Vietor [14] have shown that it was soluble in water up to 1% by weight. Each of the samples containing the additives was handled... 

Sterling, R. E. Goldberg, E. P. Thermoplastic Polymers with Dispersed Fluorocarbon Additives. US Patent 6,541,558, April 1, 2003. 

Fluorocarbon additives are added to polyolefins to prevent melt fracture during film extmsion. The efficiency of these additives depends on composition, especially in respect to fillers and antiblocking additives (e.g., diatomaceous earth, synthetic silica, and talc). Studies of antiblocking compounds with fluoro-... 

Surface adhesion of polyester was controlled by a combination of parameters such as molecular weight of polyester, concentration of hydroxyl groups, and concentration of fluorocarbon additive. To eliminate surface defects, the amount of additive should be increased, but its increase contributes to the loss of adhesion between basecoat and primer. 

Talcs are not as porous as S5mthetic silica and they most likely absorb a slip agent due to the process conditions. Figure 9.3 shows that extensive mixing increases absorption of fluorocarbon additive (die pressure is not affected by... 

Transmittance and clarity of linear low density polyethylene containing fluorocarbon additive does not change for all practical purposes (Figure 10.26). Figures 10.27 and 10.28 show data on frequently used combination of emcamide and... 

The reaction of OF2 and various unsaturated fluorocarbons has been examined (35,36) and it is claimed that OF2 can be used to chain-extend fluoropolyenes, convert functional perfluorovinyl groups to acyl fluorides and/or epoxide groups, and act as a monomer for an addition-type copolymerization with diolefins. 

The polymei latex is then coagulated by addition of salt oi acid, a combination of both, oi by a fiee2e—thaw process. The cmmb is washed, dewatered, and dried. Since most fluorocarbon elastomer gums are sold with incorporated cure systems, the final step in the process involves incorporation of the curatives. This can be done on a two-roU mill, in an internal mixer, or in a mixing extmder. 

The manufacture of the majority of fluorocarbon elastomer gums includes the addition of an incorporated cure system comprising an organic onium cure accelerator, such as triphenylbenzylphosphonium chloride [1100-88-5] and a bisphenol cross-linking agent, such as... 

Extruded Articles. In extmded article compounding, the most important parameters are scorch safety and flow characteristics (53). The bisphenol cure system again offers the best scorch resistance of the available fluorocarbon elastomer cure systems. Good flow characteristics can be achieved through proper selection of gum viscosities. Also, the addition of process aids to the formulation can enhance the flow characteristics. Typical formulations for extmsion grade fluorocarbon elastomers are given iu Table 7. 

Honeywell Specialty Materials, a 3.5 billion strategic business group of the Honeywell Corporation, is a global leader in providing customers with high-performance specialty materials, including fluorocarbons, specialty films and additives, advanced fibers and composites, customized research chemicals, and electronic materials and chemicals. Our products can be found in items you use everyday — at work and at home. For additional information, please visit www.honevwell.com/sites/sm. 

Unsaturated fluorocarbons are much more reactive toward nucleophiles than then hydrocarbon counterparts owing to fluorme s ability to both stabihze carban ions and mductively increase the electrophihcity of multiple bonds and aromatic nngs Nucleophihc attack dominates the chemistry of unsaturated fluorocarbons, and the role of fluonde ion in fluorocarbon chemistry is analogous to that of the proton in hydrocarbon chemistry [129] Like the related electrophilic reactions for hydrocarbons, there are fluonde-promoted isomenzations and dimenzations (equation 9), oligomenzations (equation 10), additions (equation 11), and amomc Fnedel-Crafts alkylations (equation 12) that all proceed via carbamomc intermediates [729 7 7]... 

A new concept in graphite disks includes addition of a fluorocarbon film barrier between the process and the disk, and is termed a duplex disk. These disks are suitable for temperatures to 392°F, with accuracies as just mentioned. 

Between 250 and 450°F (121 and 232°C), plastics used include glass or mineral-filled phenolics, melamines, alkyds, silicones, nylons, polyphenylene oxides, polysulfones, polycarbonates, methylpentenes, fluorocarbons, polypropylenes, and diallyl phthalates. The addition of glass fillers to the thermoplastics can raise the useful temperature range as much as 100°F and at the same time shortens the molding cycle. 

Chlorinated polyether is formulated particularly for products requiring, good chemical resistance. Other materials exhibiting good chemical resistance include all of the fluorocarbon plastics, ethylpentenes, polyolefins, certain phenolics, and diallyl phtha-late compounds. Additives such as fillers, plasticizers, stabilizers, colorants, and type catalysts can decrease the chemical resistance of unfilled plastics. Certain chemicals in cosmetics will affect plastics, and tests are necessary in most cases with new formulations. Temperature condition is also very important to include in the evaluation. Careful tests must be made under actual use conditions in final selection studies. 

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