Showing papers on "Polymer blend published in 1979"

Fourier‐transform infrared studies of polymer blends. III. Poly(β‐propiolactone)‐poly(vinyl chloride) system

Abstract: Fourier-transform infrared (FTIR) studies of the poly(ϵ-caprolactone) (PCL)–poly(vinyl chloride) (PVC) blend system are presented. The results indicate that there are specific interactions between the PCL and PVC in both the molten and solid states which could be responsible for the apparent compatibility of the amorphous component of these blends. Additionally, FTIR difference spectra are presented to illustrate the potential of this technique for following the kinetics of crystallinity in polymer blend systems.

Heat sealable laminated propylene polymer packaging material

Abstract: A packaging material having an excellent seal packaging property, which comprises (A) a base layer consisting of a stretched film made of a polymer composition comprising a propylene polymer and (B) a surface layer consisting of a stretched film made of a polymeric mixture comprising a polymer blend provided on at least one surface of said base layer, said polymer blend comprising a copolymer of ethylene and propylene and a copolymer of butene and any other polymerizable monomer having an ethylenic unsaturation in a weight proportion of 5:95 to 95:5.

Polyester compositions for gas and moisture barrier materials

Abstract: Polymer blends of a polyester and polyvinyl alcohol, or their copolymers, may be fabricated into barrier packaging materials having very low permeabilities to oxygen, other fixed gases and moisture.

Modeling of tensile properties of polymer blends: PPO/poly(styrene-co-p-chlorostyrene)

Abstract: Young’s modulus, yield (break) strength, and elongation to yield (break) have been measured for blends of poly(2,6‐dimethyl‐1,4‐phenylene oxide) (PPO) with polystyrene (PS), poly(p‐chlorostyrene) (PpClS), and random copolymers of styrene and p‐chlorostyrene (pClS). The significant difference between blend compositions is the compatibility of PPO with each styrene polymer. Blends of PPO with PS or copolymers with 67.1 mole% or less pClS are compatible (i.e., one Tg) and show small synergistic maxima in modulus, strength, and elongation as a function of PPO composition. These maxima correspond to observed maxima in packing density as a result of specific interactions contributing to blend compatibility. A rule of mixtures for one‐phase systems with an adjustable compatibility parameter gives adequate fit to the observed composition dependence of the modulus. In a narrow composition range between 67.8 and 68.6 mole% pClS, copolymers exhibit partial miscibility with PPO. Two mixed composition phases are present. Moduli of these transitional blends follow the same form of synergistic dependence on blend composition as do the compatible blends but strength and elongation exhibit a sigmoidal relation to blend PPO content. At about 20% PPO, strength (and elongation) reaches a minimum as predicted by a simple composite model for a dispersed phase with good adhesion to the matrix. A maximum is reached at ∼80% PPO at which composition blend test specimens yield prior to failure. Blends of PPO with PpClS and with copolymers of ≳68.6 mole% pClS exhibit a broader minimum in strength (and elongation) but a similar maximum at 80% PPO. Unlike the compatible and transitional blends, moduli follow a nonsynergistic composition dependence adequately represented by the series model for two‐phase systems.

Crystalline/crystalline polymer blends: Some structure–property relationships

Abstract: Mechanical properties, morphology, and compatibility of polybutene-1 blended with polypropylene, both crystallizable polymers, are described in the present study. Blends of various compositions were studied using tensile tests, differential scanning calorimetry, wide-angle x-ray diffractometry, and optical microscopy. A discussion on the state of compatibility and structure–property relationships for such blends in presented.

Cold drawn film made of an ethylene polymer blend composition

Abstract: A composition for shrinkable film which excels in heat-sealability, transparency, strength, and particularly low-temperature quick shrinking property and, therefore, suits production chiefly of packaging materials, a film made of the composition and a process for the manufacture of the film are disclosed. Specifically, the composition comprises one of the specific combinations of components (A), (B) and (C), i.e. the combinations of (A)+(B), (B)+(C) and (A)+(B)+(C), wherein (A) is non-rigid polyolefine resins such as ethylene vinyl acetate, (B) is an elastomer comprising a specific ethylene-α-olefin copolymer, and (C) is rigid polyolefin resins such as polypropylene. The packaging film excelling particularly in optical property, mechanical strength and low-temperature shrinking property is obtained by converting a homogeneous blend of the aforementioned composition, either in its crosslinked form or in its non-crosslinked form, into a tubular raw film, which is stretched at a temperature low enough for imparting a high orientation to the film. The process for the manufacture of this packaging film is also disclosed.

Synthesis and physical properties of blends of donor polymers from 2-(p-dimethylaminobenzyl)-1,3-propanediol and acceptor polymers from 2-(3,5-dinitrobenzyl)-1,3-propanediol: A new phase composed of donor and acceptor polymers.

Abstract: Donor (or acceptor) poly(carbonate)s or poly(phthalate)s were prepared from 2-(p-dimethylaminobenzyl)-1,3-propanediol (or from 2-(3,5-dinitrobenzyl)-1,3-propanediol). The spectral, thermal, mechanical, and optical properties were measured for the donor polymers, the acceptor polymers, and their blends in order to clarify the effects of the formed electron-donor-acceptor (EDA) complexes. The donor and acceptor polymer blends were found to consist of two-phase structures by differential scanning calorimetry, torsional braid analysis, and scanning electron microscopy. It was noticed that the tensile modulus of the polymer blends was larger than that of each component polymer. The increased mechanical strength was interpreted in terms of the EDA interaction on the boundaries between globules and surroundings.

Soft ethylenic polymer blend foams

Abstract: Low density, closed cell, soft foam products having dimensional stability are made from ethylenic resin blends having low stiffness by extrusion foaming, wherein the heat plastified gel comprises the ethylene polymer blend and at least one volatile blowing agent. The blends especially comprise a copolymer of ethylene and monoethylenically unsaturated carboxylic acid and a copolymer of ethylene and at least one monoethylenically unsaturated non-ionic comonomer. The starting ethylenic resin blends are preferably blends of ethylene acrylic acid copolymers and ethylene vinyl acetate copolymers, having stiffness less than about 20,000 psi. Exemplary volatile blowing agents are 1,2-dichlorotetrafluoroethane, 1-chloro-1,2,2,2-tetrafluoroethane and 2,2-difluoropropane.

Polyamide/block copolymer blends

Abstract: A polymer blend having excellent impact strength, even at zero moisture level, comprises the blend of 100 parts by weight of a polyamide and less than 50 parts by weight of a selectively hydrogenated monoalkenyl arene-conjugated diene block polymer

Vinyl chloride polymer blend composition

Abstract: The present invention provides a vinyl chloride polymer composition comprising an intimate mixture of a first vinyl chloride polymer containing a sulfide linkage in the molecular chain and a second vinyl chloride polymer having a higher molecular weight than the first polymer, and a process for producing a first vinyl chloride polymer for use in the composition, comprising polymerizing vinyl chloride or a mixture of vinyl chloride and an ethylenically unsaturated monomer in the presence of a free radical initiator using as a chain transfer agent a mercapto compound or a disulfide compound. Said vinyl chloride polymer composition has been improved in heat stability and processability.

Thermally insulating tubes

Abstract: A blend of high and low density polyethylene and azodicarbonamid added as blowing agent is heated in an extruder to a temperature above the melting point of the high density component and fed to a shear head having a hollow rotating mandrel through which tubing is fed for depositing thereon a hose at the nozzle exit of the head. A peroxide is fed to the shear head for mixing with the polymer blend and immediately initiating crosslinking; blowing begins just prior to the depositing, the material being already crosslinked to a considerable extent.

High impact thermoplastic blend useful for injection moulding - contains hard styrene!-acrylonitrile! copolymer, graft ABS and graft acrylic!-ester! copolymer

Abstract: Polymer blend is based ona hard component (A) and 2 graft copolymers (b) and (c). (A) consists of copolymer(s) of styrene and/or alpha-methylstyrene with 20-40 wt. % acrylonitrile (AN); (b) of (Bl) 40-80 (50-60)% butadiene polymer of average particle size 0.20-0.45 (0.26-0.35) mu m and (B2) 20-60 (40-50)% grafted mixt. of styrene and AN in 75:25 to 65:35 ratio; and (c) of (Cl) 40-80 (70-60)% crosslinked acrylic ester polymer, with Tg below 0 degree C and average particle size 0.05-0.15 (0.06-0.08) mu m, and (C2) 20-60 (30-40)% grafted mixt. of styrene and AN in 75:25 to 65:35 ratio. The ratio of (B1) to (Cl) is 70:30 to 30:70 (60:40 to 50:50) and the amt. of (B1 + Cl) in the blend ca. 10-35 (15-30)%. The blend can also contain conventional additives, esp. ethylene and/or propylene oxide polymer or a dyestuff or coloured pigment. Mouldings with high (cold) impact strength and good surface structure and good processing properties are obtd..

Polyphenylene oxide blending

Abstract: Polyphenylene oxide is blended with conjugated diene polymer by first producing a polymer mixture of polyphenylene oxide and conjugated diene polymer by solution blending and then mechanically blending the so produced masterbatch with the conjugated diene polymer.

Effects of dispersion on flow and mechanical properties of polymer blends

Abstract: Blends of linear polyethylene and ethylene-propylenediene elastomer, representing the entire composition range, were prepared under various conditions of shear intensity. It was found that both viscoelastic flow parameters and mechanical properties at large deformation respond strongly to variations in shear history of material preparation. Mechanical degradation of the polymers not being detected, it is postulated that property variations are due to morphological effects related to domain sizes of the two components and to the ease of molecular diffusion across domain boundaries. Thus, mechanical properties develop over finite times of mixing, consistent with the attainment of steady states in domain sizes. Maximum sensitivity of mechanical properties to mixing variables is found for 50/50 blends of the polymers, which have maximum interdomain contact areas. It appears feasible to develop desired balances of flow and mechanical properties in such polyblends through the close control of component dispersion processes.

Coating compositions comprising polymer blends

Abstract: OF THE DISCLOSURE Coating compositions comprising intimate blends of a polyvinyl acetal, an alkoxymethyl polyaminotriazine and an oligomeric polystyrene or poly(.alpha.-methylstyrene). The coating compositions may contain up to 500 parts by weight of an inert non-photoconductive pigment per 100 parts by weight of polymer blend. The compositions are useful for the preparation of electrographic recording media which possess improved resistance to curl under variable conditions of humidity.

Light-polarizing film

Abstract: A light-polarizing film comprising a polymer mixture containing a polymer having polyene chains formed by partial dehydrohalogenation of a halogenated vinyl polymer or a halogenated vinylidene polymer and one or more of the polymers selected from the group consisting of acrylate polymers and methacrylate polymers. Said light-polarizing film has excellent heat stability as well as humidity resistance and is useful in various fields including liquid crystal device, optical device, etc.

Phase equilibria in multicomponent polymer mixtures

Abstract: In recent years thermodynamic equilibrium properties of amorphous polymer blends have been the subject of increasing interest. Experimental techniques, known in the study of polymer solutions, have been applied to blends and have been modified to deal with highly viscous systems. Determination of critical points, spinodal and cloud-point curves are now well possible by means of a low-speed centrifuge, pulse induced critical scattering and the centrifugal homogenizer. The classic Flory-Huggins model cannot describe the experimental results. Improvements can be made by the introduction of the contact surface areas of the segments, and by correcting the combinatorial entropy of mixing for orientational effects related to chain flexibility. Two-peaked spinodals may furthermore be described with a model accounting for three concentration ranges in the blend, the two dilute solutions of one polymer in the other and an intermediate range of uniform segment density. As a third possibility the introduction of holes in the lattice (simple lattice gas) can also lead to qualitatively correct descriptions, even in those cases where the phase diagram is still more complex (system poly(styrene-co-acrylonitrile)/polymethylmethacrylate) and shows three miscibility gaps. Strictly-binary polymer mixtures with a bimodal cloud-point curve should show two stable critical points. The fact that we did not find more than one may be attributed to polydispersity which easily shifts one of the critical points into the experimentally inaccessible meta-stable region.

Injection moulding process using polymer blends containing high molecular polyethylene of high density

Abstract: Process for producing injection moulded parts having markedly improved mechanical strength properties wherein a blend of high molecular polyethylene having high density with a matrix material which consists of a polymeric material with which the high molecular polyethylene has a limited compatibility is injection moulded at high injection moulding pressures exceeding 250 MPa, whereby a fibre reinforced injection moulded article having improved mechanical properties is produced

Ternary polymer blends

Abstract: A thermoplastic composition comprising 30 to 90 weight percent of a block copolymer formed from a conjugated diene and a monovinylarene, 5 to 35 weight percent of an ethylene-propylene-nonconjugated diene terpolymer, and 5 to 30 weight percent of a thermoplastic polyolefin. The blend exhibits good distortion resistance, solvent resistance, high temperature retention of hardness, and ozone resistance.

Mie scattering from sphere structures in polymer blends

Abstract: Polymer blends of transparent poly(methyl methacrylate) and polystyrene become opaque due to light scattering at the boundaries of the two polymers. The polymer blend is light brown when it is illuminated by white light. The coloring depends on the spherical domain structures existing in the polymer blend. The coloring was analyzed by using the rigorous Mie theory. The Mie results were compared with the semiempirical results previously reported by the authors. The wavelength dependence of theoretical scattering efficiencies on radii of scattering spheres from 0.05 to 1.2 μm was obtained for polystyrene spheres in poly(methyl methacrylate) matrix, and vice versa. The scattering at the short wavelength region is stronger than at the long wavelength region. The scattering efficiencies become almost constant in the visible wavelength region for sufficiently large spheres.

Manufacturing of thermoshrinking polyamide film

Abstract: PURPOSE:To obtain a film excellent in oxygen barrier and heat resistance by subjecting polymers each containing a specific quantity of constituent units obtained from xylenediamine constituents and alpha, omega- aliphatic dicarboxylic acid having carbon atoms of 6 through 12, in molecular chain, to simultaneous biaxial elongation. CONSTITUTION:Thirty to one hundred % by weight of a polymer containing 50 molar % or more of constituent units consisting of one member of more of meta or paraxylenediamine constituents and alpha, omega- aliphatic dicarboxylic acid having carbon number of 6 through 12, in a molecular chain, and a polymer mixture containing 70% or less by weight of aliphatic polyamide, is molten and extruded. After cooling, these polymers are subjected to the simultaneous biaxial elongation at the elongation speed of more than 100,000%/min or more, at a temperature of 70 through 140 deg.C under the multiplication ratio of length and width, 3.5-5.5 times, and cooled. For example, nylon salt of adipic acid of metaxylenediamine and salts of adipic acid of bispropylamine derivatives of polyethylene glycol are polymerized.

The characteristic features of sulphur containing polymers. A review

Abstract: The properties of carbon and hetero-chain polymers containing sulphur as -S-, Sn, SO2, SO, and SH are discussed. The effects of the composition of such polymers on their physico-chemical, thermal, photo-chemical, radiation-chemical and complexing properties are examined. The high reactivity of sulphur and its compounds, the mobilities of the S-S and C-S bonds, make it possible to use them in the synthesis and process technology of polymers with defined properties, and in the modification of the properties of differing type of polymers. The stabilizing action of optimal quantities of containing fragments in the macromolecule, or of S containing additives to polymer blends are typical cases of the earlier established general principles, namely the termination of chain decomposition reactions and of structuration by the radicals which are produced in the system under extreme conditions. The polysulphides have selective complex forming properties which depend on their composition and apply to heavy as well as precious metals.

Blends of copolyimides with copolyamideimides

Abstract: Novel polymer blends are disclosed comprising about 10 to 95 percent by weight of a copolyimide (A) prepared from benzophenone-3,3',4,4'-tetracarboxylic acid dianhydride and a mixture of 4,4'-methylenebis(phenyl isocyanate) and toluene diisocyanate (2,4- or 2,6-isomer or mixtures thereof) with the isocyanates used in a molar percent ratio from about 10/90 to 30/70 respectively; and from about 90 to 5 percent by weight of a copolyamideimide (B) prepared from 4,4'-methylenebis(phenyl isocyanate) and a mixture of trimellitic anhydride and isophthalic acid with the acid components used in a molar percent ratio from about 70/30 to 90/10 respectively. The novel blends may be used in the form of their dry blend or in solution and the films produced therefrom are characterized by improved elongation and tear strength values over those for the copolyimide (A) alone. Furthermore, the softening point of the blends is increased over the copolyamideimide alone.

Polyvinyl chloride - ethylene oxide polymer blends and methods of modifying the impact and melt flow properties of polyvinyl chloride

Abstract: In the modification of the properties of polyvinyl chloride (PVC). such as impact resistance and melt flow, polymers derived from monomer systems comprising at least 80% by weight ethylene oxide and free of pendant epoxy groups along the polymer chain are blended with PVC. The modifying ethylene oxide polymer may be crosslinked with a symmetrical diepoxide