| 摘要 |
Briefly, in one aspect, this invention provides a melt-processable composition comprising, in admixture: (1) one or more melt-processable thermoplastic hydrocarbon polymers as the major component of the composition by weight, and, as a minor component of the composition by weight; (2) an effective amount of a chemically-resistant, fluoropolymer process aid to improve the processability of the composition. The fluoropolymer process aid contains at least about 50 weight percent of fluorine and comprises one or more fluoropolymers which are essentially completely ethylenically saturated and consist essentially of interpolymerized units derived from the following monomers: (a) one or more fluorinated olefin monomers having the following general formula: CF2=CXR1 wherein X is a hydrogen or a halogen atom; and R1 is a halogen atom or is an alkyl, cyclic alkyl, or aryl group having from 1 to 10 carbon atoms, and preferably it is either a halogen atom or a group having 1 to 2 carbon atoms; R1 groups may contain one or more heteroatoms such as nitrogen or oxygen and may be partially-, fully- or non-halogenated, provided, however, that whenever X is a hydrogen atom, R1 contains an allylic carbon atom relative to the .alpha.-unsaturation and that allylic carbon atom is not perfluorinated; (b) one or more olefin monomers of the general formula: CH2=CXR2 wherein X is a hydrogen or a halogen atom; and R2 is a hydrogen or a halogen atom with the proviso that R2 and X are not both fluorine; R2 may also be an alkyl, cyclic alkyl, or aryl group having from 1 to 10 carbon atoms, and preferably is a hydrogen atom or a group having 1 to 2 carbon atoms; and R2 may be partially-, fully- or non-halogenated and may contain one or more heteroatoms such as oxygen or nitrogen; and (c) 0 to 15 weight percent, of the total weight of the fluoropolymer, of one or more monomers that produce an acidic hydrogen on the backbone of the resulting fluoropolymer after polymerization. Component (2) has a Carreau-Yasuda Equation m1 parameter of about 0.7 or less, and the ratio of the melt viscosity of component (2) to the melt viscosity of component (1) is between about 0.01 and 100 at the melt processing conditions of the composition. The above-described admixture of components (1 and 2) may also be admixed with other conventional additives and adjuvants, such as fluorinated and non-fluorinated process additives, light stabilizers, antioxidants, fillers, antiblocking agents, and pigments. In another aspect, the present invention provides compositions such as those described above that further comprise one or more poly(oxyalkylene) polymers. Methods using these compositions to improve the processability of a meltprocessable thermoplastic hydrocarbon polymer are also disclosed.
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