Showing papers on "Polymer blend published in 1974"

Studies on polymer blend of nylon 6 and polypropylene or nylon 6 and polystyrene using the reaction of polymer

Abstract: In the presence of maleic anhydride-grafted polypropylene, marked dispersibility of the polymer blend of isotactic polypropylene and nylon 6 was obtained. This appeared to be caused by the formation of a certain graft polymer between maleic anhydride in polypropylene and terminal amino groups of nylon 6. The same phenomenon was observed when polystyrene and nylon 6 were blended with styrene–methacrylic acid copolymer as the interpolymer. The existence of such a graft polymer was confirmed by solvent extraction, estimation of the amino group of nylon 6, and identification by differential scanning calorimetry. The physical properties, especially mechanical properties of nylon 6–polypropylene polymer blends, were remarkably improved with increase of maleic anhydride added to the polymer blend. On the other hand, the physical properties those of nylon 6–polystyrene polymer blends were very little improved even in the presence of good dispersibility.

Ethylene polymer blend and polymerization process for preparation thereof

Abstract: A high density ethylene polymer blend having improved impact strength and environmental stress crack resistance comprises a high molecular weight, non-elastomeric ethylene/propylene copolymer having a crystallinity of at least 5 percent and an intermediate molecular weight, high density ethylene polymer. The improved ethylene polymer blend is provided by a dual zone, low pressure, Ziegler solution polymerization process wherein (1) ethylene and propylene are copolymerized at a low pressure and solution temperatures in presence of a titanium-containing catalyst in an auxiliary polymerization zone, (2) ethylene is polymerized in a primary polymerization zone at low pressure and solution temperature in the presence of a titanium-containing catalyst and (3) the resulting solutions of the reaction products of both zones are combined to form an essentially homogeneous mixture.

Recent advances in polymer blends, grafts, and blocks

Abstract: Section I. Introduction.- An Introduction to the Synthesis of Block- and Graft Copolymers.- Practical Properties of Multi-Phase Polymer Systems.- On the Generation of Novel Polymer Blend, Graft, and IPN Structures through the Application of Group Theory Concepts.- Effects of Monomer Unit Arrangement on the Properties of Copolymers.- Block Copolymer Theory. II. Statistical Thermodynamics of the Microphases.- Cationic Grafting: The Synthesis and Characterization of Butyl Rubber-g-Polystyrene and PVC-g-Polyisobutylene.- Synthesis, Morphology, and Properties of AB Crosslinked Copolymers.- Section II. Introduction.- Polysulfone-Nylon 6 Block Copolymers and Alloys.- Dynamic Mechanical Properties of Urea-Urethane Block Polymers.- Orientation Studies of Polyurethane Block Polymers.- Butadiene-Styrene AB Type Block Copolymers.- New Developments in Block Copolymer Applications.- Polystyrene-Poly (?-Methyl Styrene) AB Block Copolymers and Alloys.- Section III. Introduction.- The Synthesis, Characterization and Physical Properties of EPM-g-Polystyrene Thermoplastic Elastomers.- The Causes of Pitting and Haze on Molded ABS Plastic Surfaces.- Poly(Butadiene-Co-Styrene)/Polystyrene IPN's, Semi-IPN's and Graft Copolymers: Staining Behavior and Morphology.- Topologically Interpenetrating Polymer Networks.- Time-Temperature Superposition in Two-Phase Polyblends.- Contributors.

Antistatic polymer blend

Abstract: An antistatic polymer blend comprising a synthetic polymer and an antistatically effective amount of a compound of the formula: ##EQU1## wherein R is alkyl of 4 to 18 carbon atoms unsubstituted or substituted by halo or aryl

New Methods for Electron Microscopy of Polymer Blends

Abstract: Two new methods of sample preparation have been developed for electron microscopical examination of polymer blends. The first is an ebonite method where the blend is hardened in a sulfur-s...

EPDM polymers grafted with vulcanization accelerators

Abstract: Preparation of ethylene-higher Alpha -olefin-polyene (EPDM) polymers having grafted thereon vulcanization accelerators and polymer blends with highly unsaturated diene rubbers that are cured using sulfur are disclosed. The vulcanizates exhibit improved properties compared to polymer blends of EPDM and diene rubbers.

Polyolefin-elastomer compositions

Abstract: A multilayer composition may be prepared by a process comprising applying an intimately mixed blend of a thermoplastic polyolefin and an elastomer to the surface of an elastomer and bonding said blend to said surface by heating and application of pressure. Thus a film of the intimately mixed blend may be applied to the surface of the elastomer. Also a motor-car door seal can be produced by extruding to the desired profile the intimately mixed blend of thermoplastic polyolefin and elastomer so as to form the base foot and bonding the elastomer seal to the extruded section.

Vulcanizates of EPDM and diene rubber blends

Abstract: Polymer blends of ethylene-higher α-olefin-polyene (EPDM) polymers with highly unsaturated diene rubbers are cured using sulfur and a N,N-(higher alkyl) thiocarbamylsulfenamide as a vulcanization accelerator. The vulcanizates exhibit improved tensile strength, flex-heat build-up, and oil swell properties.

Degradation of polymer mixtures. IV. Blends of poly(vinyl acetate) with poly(vinyl chloride) and other chlorine‐containing polymers

Abstract: The degradation of the binary polymer blends, poly(vinyl acetate)/poly(vinyl chloride), poly(vinyl acetate)/poly(vinylidene chloride) and poly(vinyl acetate)/polychloroprene has been studied by using thermal volatilization analysis, thermogravimetry, evolved gas analysis for hydrogen chloride and acetic acid, and spectroscopic methods. For the first two systems named, strong interaction occurs in the degrading blend, but the polychloroprene blends showed no indication of interaction. In the PVA/PVC and PVA/PVDC blends, hydrogen chloride from the chlorinated polymer causes substantial acceleration in the deacetylation of PVA. Acetic acid from PVA destabilizes PVC but has little effect in the case of PVDC because of the widely differing degradation temperatures of PVA and PVDC. The presence of hydrogen chloride during the degradation of PVA results in the formation of longer conjugated sequences, and the regression in sequence length at high extents of deacetylation found for PVA degraded alone is not observed.

Polyvinyl alcohol microgel precursor blends

Abstract: Stable, fluid polyvinyl alcohol-containing microgels in water having a Brookfield viscosity of 115 to 1000 centipoises may be prepared more economically from a dry blend which comprises (A) a polymer mixture consisting of at least about 05% by weight of polyvinyl alcohol and one or more polysaccharide selected from the group consisting of up to about 995% by weight of starch and up to about 33% by weight of sodium carboxymethylcellulose, said polyvinyl alcohol having a Hoeppler viscosity of about 4 to 150 centipoises and having at least about 50 mole percent of the monomeric units present as vinyl alcohol units, (B) water-soluble, solid titanium salt of a hydroxy carboxylic acid of 2 to 10 carbon atoms in an amount which provides about 005 to 10 parts by weight of tetravalent titanium ions per 100 parts of polymer mixture, and (C) about 005 to 20 parts by weight of water-soluble, solid hydroxy carboxylic acid of 2 to 10 carbon atoms per 100 parts of polymer mixture

Oil or organic solvent-absorbent

Abstract: An oil or organic solvent-absorbent is prepared by extruding a molten thermoplastic resinous polymer blend of polystyrene and polyethylene containing a foaming agent through a die having a slit aperture of 0.1 - 1.0 mm width, quenching the extrudate at the die exit to a temperature below the glass transition point of the resinous blend, drafting the extrudate at a draft ratio from the maximum draft ratio possible under the operating conditions to one-third the maximum draft ratio, laminating at least two sheets of the resulting unopened, sheet-like reticulated structure having numerous non-continuous cracks along one direction so that the direction of the cracks of each such sheet is the same, pulling the laminate in a direction perpendicular to the direction of the cracks to separate the constituent fibers from each other, and crimping the opened, sheet-like laminate either alone or together with at least one other sheet-like material; a process for removing oil or organic solvents with the absorbent product.

Thermo-Optical Analysis of Poly(2,6-disubstituted-1,4-phenylene Oxide) Blends

Abstract: Mobility transitions closely related to the glass transitions of three binary polymer-polymer blend systems have been determined by thermo-optical analysis (TOA). TOA in this instance consists of the automated observation of birefringence relaxation in scratched transparent polymer and polymer blend films during their programmed heating. The blend systems studied were: I. polystyrene (PS) + poly (2,6-dimethyl-1,4-phenylene oxide) (PMMPO); II. poly (2-methyl-6-phenyl-1,4-phenylene oxide) (PMPPO) + PMMPO; and III. PS + PMPPO. Blend Systems I and II display a single TOA transition temperature at each blend composition indicating homogeneity and true thermodynamic compatibility of the polymer pairs. Blend System III displays two TOA transition temperatures at each blend composition indicating incompatibility and resultant liquid-liquid phase equilibration in molten mixtures of PS and PMPPO. The shapes of the transmitted light intensity vs temperature curves for scratched PS + PMMPO films between 90° ...

Two-Dimensional Model of Mechanical Properties of Polymer Blends: Application to Polypropylene and Polyethylene Blends

Abstract: Two new mechanical models for the description of mechanical properties of two-component polymer blends are proposed. On the basis of these models the dependence of the dynamic complex moduli on the blend content is theoretically calculated. Results obtained theoretically are compared with experimental data for polyethylene and polypropylene blends.

Radiation crosslinked block copolymer blends with improved impact resistance

Abstract: Polymer blends having high impact resistance after mechanical working are produced by blending together a non-elastomeric monovinylidene aromatic polymer such as polystyrene with an elastomeric copolymer, such as a block copolymer of styrene and butadiene, in the form of crosslinked, colloidal size particles.

Rapid assessment of weathering stability from exposure of polymer films. III. Relative weathering stability of ABS and arylon, a related polymer blend

Abstract: Arylon, a blend of an aromatic polysulfone and a terpolymer of acrylonitrile–butadiene and α-methylstyrene, weathers similarly to ABS. However its first-order rate constant for the loss of unsaturation is only 0.39 cm2(Wh)−1 as against 0.80cm 2(Wh)−1 for ABS. This slower weathering is probably caused by the decrease in light intensity penetrating Arylon compared with ABS as a result of the high degree of light scattering observed in the former.

Vulcanizable polymer blends of a halogen-containing polymer and a carboxyl-containing polymer

Abstract: Polymer blends of a halogen-containing polymer and a carboxyl-containing polymer are covulcanized using as the cure system (1) a metal oxy compound and (2) a quaternary ammonium salt or a monofunctional tertiary amine. The vulcanizates exhibit excellent physical properties, and are useful in fabricating hose, belting, gaskets, o-rings, and the like.

Flame resistant thermoplastic blend

Abstract: Thermoplastic blends of polyurethane polymers, chlorinated polyethylene polymer, optionally polyethylene resins and antimony trioxide, and a flame retardant selected from 1,2,3,4,7,8,9,10,13,13,14,14-dodecachloro-1,4,4a,6a,7,10,10a,12a-octahydro-1,4:7,10-dimethanodibenzocyclooctane, 1,2,3,4,5,6,7,8,10,10,11,11-dodecachloro-1,4,4a,4b,5,8,8a,9a-octahydro-1,4:5,8-dimethanodibenzofuran, 6-(1',4',5',6',7',7'-hexachloronorborn-5'-en-2'-yl)-1,2,3,4,10,10-hexachloro-1,4,4a,5,6,7,8,8a,-octahydro-1,4:5,8-dimethanonaphthalene, and 6-(1',4',5',6',7',7'-hexachloronorborn-5'-en-2'-yl)-1,2,3,4,10,10-hexachloro-1,4,4a,5,6,7,8,8a-octahydro-1,4-methanonaphthalene, are flame resistant and also essentially retain the good physical properties of a polyurethane-chlorinated polyethylene polymer blend not containing a flame retardant.

Highly flame-retardant shaped articles and method for preparing the same

Abstract: Shaped articles such as fibers and films having durable, highly flame-retardant property comprising a halogen-containing polymer and polyvinyl alcohol including its acetal, as principal constituents, and tin substantially in the form of stannic acid. Said shaped articles are produced by a method (A) comprising subjecting shaped articles such as polymer blend fibers containing a halogen-containing polymer and polyvinyl alcohol, as principal constituents, to acetalization in an acetalizing bath containing a tin salt of a strong acid, and converting it to stannic acid substantially afterwards by increase of pH in the articles; alternatively by a method (B) comprising blending an aqueous solution of polyvinyl alcohol, an emulsion of a halogen-containing polymer and an aqueous dispersion of stannic acid or stannic acid anhydride, and subjecting the resulting solution of the polymer blend to emulsion spinning technique; or by a method (C) comprising treating shaped articles such as polymer blend fibers containing, as principal constituents, a halogen-containing polymer and partially acetalized polyvinyl alcohol, with an aqueous solution of a tin salt of a strong acid and converting it to stannic acid substantially afterward by increase of pH in the shaped articles.

Polymer compatibility III. The system poly(methyl methacrylate)–poly(vinyl acetate). Characterization studies

Abstract: Blends of poly(methyl methacrylate) (PMMA) and poly(vinyl acetate) (PVAc) were prepared by mixing the polymers in the melt and in the absence of a solvent. PMMA was the major constituent of the blend. The polymer blends were tested, using various methods, to determine if they are compatible as solids. Data obtained from dynamic mechanical and DSC measurements show that, when they are mixed under given Brabender mix conditions, the blends exhibit properties characteristic of polymer pairs compatible as solids. If the mix conditions are altered, a two-phase system is evidenced. Using micrographs obtained by light microscopy in phase contrast as criteria, two companion blends containing PMMA/PVAc 80/20 would be classified as incompatible as solids because of the differences in refractive index of PMMA and PVAc. The micrographs also show that, in the system that would otherwise be listed as compatible, the PVAc domains appear to be relatively uniform in size and distribution through the PMMA matrix. In its companion blend, large, irregularly shaped particles of PVAc which are poorly dispersed in the PMMA matrix are evident.

On the Generation of Novel Polymer Blend, Graft, and IPN Structures through the Application of Group Theory Concepts

Abstract: Polymer blends, grafts, and blocks have achieved importance as toughened plastics and novel elastomers because of their complexity, not in spite of it. By definition, these materials are characterized as some intimate combination of two (or more) kinds of polymer molecules. Because of the very small entropy gain on mixing long polymer chains, and the usually encountered positive heat of mixing, most polymer blends, grafts, and blocks form two phases. Most strikingly in these materials, the exact mode of synthesis controls the two-phase morphological features, which in turn influences their mechanical behavior. Thus a one-to-one relationship exists between synthetic detail and potential application.

Vinyl monomer polyurethane graft copolymers - used as adhesion aids

Abstract: A graft copolymer comprises 90-30 wt.% of a thermoplastic, predominantly linear polyurethane (e.g. derived from polycaprolactone and 4,4-diphenylmethanediisocyanate) as back-bone polymer, and 10-70 wt.% of polymers of monoethylenically unsatd, vinyl cpds (e.g styrene), chemically bonded, as side chains, to the backbone polymer. Prepn may be by graft copolymsn. with the aid of radical catalysts or high-energy radiation. It is used as highly compatible a adhesion adjuvants in the adhesive bonding of polymeric materials as components in polymer blends to improve impact-resistance; and in mfr. of laminates.

The influence of stabilizers on the fusion of rigid poly(vinyl chloride)

Abstract: It is known that the fusion rate of rigid PVC in an extruder partly depends upon the lubricants that are used. In the present study it is shown that different stabilizers have a great influence upon the rate of fusion of rigid PVC. Results from extrusion experiments and the Brabender Plastograph strongly indicate that a correlation exists between rapid melting in the extruder and the melt viscosity-temperature relation of the polymer blend. The reason why certain stabilizers cause a more rapid fusion of the PVC is attributed to the chemical structure of the stabilizers.

A Practical Method for Determining the Viscoelastic Properties of Polymer Melts at High Shear Rates

Abstract: A practical method is presented for determining both the viscous and elastic properties of polymer melts over the range of shear rates which is of practical interest to various polymer operations. The method involves measurement of wall normal stress distribution along a die. The basic concept of die design (capillary/slit/annular die) is discussed, and a summary of the experimental results obtained during the past several years is presented for homopolymers, polymer blends, copolymers, and filled polymers of industrial use in various polymer operations. A new revised theory of Han is used to correctly predict the first and second normal stress difference from exit pressure measurements.

Segmented copolyester-vinyl chloride polymer compositions

Abstract: 1354826 Copolyester-vinyl chloride polymer compositions E I DU PONT DE NEMOURS & CO 18 May 1972 [19 May 1971] 23520/72 Headings C3R and C3P A polymer blend contains 5-95% by weight of a vinyl chloride polymer having a tensile modulus of at least 50,000 psi and 5-95% by weight, said percentages based on the total weight of vinyl chloride polymer and copolyester, of a thermoplastic segmented copolyester containing 5-90% by weight of ester units derived from a long chain glycol having a molecular weight of at least 600 and a dicarboxylic acid and 10-95% by weight of ester units derived from a low molecular weight diol having a molecular weight of less than 250 and a dicarboxylic acid The examples describe mixing copolyesters derived from dimethyl terephthalate, optionally with dimethyl isophthalate, polytetramethylene oxide glycol of molecular weight 980 and 1,4-butanediol with vinyl chloride homopolymer or a vinyl chloride (86%)-vinyl acetate (14%) copolymer

Mechanical Fabrication of Thermoplastic Polymers

Abstract: One of the most important features influencing the mechanical behavior of a fabricated thermoplastic item is the spatial arrangement of the polymer molecules. Inter alia processes developed for controlling the pattern of orientation of the polymer molecules are discussed.