Showing papers on "Copolymer published in 1969"

Block copolymers having reduced solvent sensitivity

Abstract: Block copolymers are provided which exhibit reduced sensitivity to organic solvents which comprise block copolymers of at least one elastomeric conjugated diene polymer block, block copolymerized with at least two monovinyl arene polymer blocks, all chains also containing either polyethylene or butadiene blocks, this latter block at least being hydrogenated to an extent sufficient to reduce the original double bonds by at least about 80 percent.

Aqueous process for making improved tetrafluoroethylene / fluoroalkyl perfluorovinyl ether copolymers

Abstract: TOUGH, STABLE COPOLYMERS OF TETRAFLUOROETHYLENE MONOMER AND FLUOROVINYL ETHER MONOMERS CAN BE PRODUCED BY AQUEOUS POLYMERIZATION OF THE MONOMERS BY A PROCESS THAT REQUIRES THAT THE REATION BE CARRIED OUT AT FROM ABOUT 50 TO 110*C. IN THE PRESENCE OF A WATER-SOLUBLE INITIATOR SUCH AS AMMONIUM PERSULFATE, AN EMULSIFYING AGENT AND A GASEOUS CHAIN TRANSFER AGENT SUCH AS HYDROGEN, METHANE OR ETHANE.

Process for the polymerization and/or copolymerization of olefins with the use of ziegler-type catalysts supported on carrier

Abstract: A PROCESS FOR POLYMERIZING AND/OR COPOLYMERIZING OLEFINS BY USING AN IMPROVED CATALYST CONSISTING OF A TRANSITION METAL COMPOUND SUPPORTED ON ELECTRONDONOR-PRETREATED INORGANIC SOLID PARTICLES TE TRANSITION METAL COMPOUND BEING A COMPONENT OF A ZIEGLER-TYPE CATALYST, AND AN ORGANOMETALLIC COMPOUND, WHEREBY THE POLYMERIZATION ACTIVITY OF THE CATALYST PER UNIT WEIGHT BOTH OF THE TRANSITION METAL AND ORGANOMETALLIC COMPONENT REMARKABLY INCREASES, THUS MAKING IT POSSIBLE TO REDUCE AN AMOUNT OF A CARRIER WHCH REMAINS IN THE RESULTANT POLYMER CAUSING INCREASED ASH CONTENT, AND ALSO POSSIBLE TO EASILY CONTROL THE MELT-INDEX OF THE RESULTANT POLYMER.

Thermodynamic interpretation of domain structure in solvent-cast films of A–B type block copolymers of styrene and isoprene†

Abstract: Electron microscopic textures of A–B type block copolymers of styrene and isoprene cast from several solvents were investigated by means of the osmium tetroxide fixation technique. The two-phase structure, i.e., the semimicro heterogeneous structure due to the microphase separation of block segments, was observed to change systematically with the fraction of block segments and the kind of solvent. Three types of fundamental domain structure were found. With the assumption that domain structure originates from micellar structure at a critical concentration in relatively dilute solution during solvent casting, the formation of the three types of domain structure and the sizes of their elements were treated in terms of the equilibria governing the formation of micelles at the critical concentration. This analysis takes into account such thermodynamic and molecular parameters as the incompatibility between the A and B segments, the solvation of the segments, the casting temperature, the total chain length of the block copolymer, and the weight fraction composition of the block copolymer. It was concluded that the block segments are preferentially oriented along the direction perpendicular to the interface between the two phases. This particular orientation-aggregation of the block segments must make the bulk properties of the block copolymer much different from those of merely mechanical mixtures of the corresponding homopolymers, even if the same semimicro heterogeneous structures are formed in the mechanical mixtures.

Conjugated diene block copolymers having a random copolymer elastomeric block and their hydrogenated counterparts

Abstract: BLOCK COPOLYMERS EXHIBITING SUBSTANTIALLY REDUCED SET AT HIGH EXTENSION AND IMPROVED RESISTANCE TO OXIDATION COMPRISE BLOCK COPOLYMERS HAVING AT LEAST TWO NON-ADJACENT HYDROGENATED BUTADIENE POLYMERS BLOCKS, EACH PAIR OF SAID BLOCKS BEING SEPARATED BY AN ELASTOMERIC RANDOM DIENE-MONOVINYL ARENE DCOPOLYMER BLOCK.

Polymerization of adsorbed monolayers

Abstract: Insertion poly(methyl methacrylate) homopolymers and copolymers with methacrylic acid were prepared from the corresponding monomers adsorbed as monolayers on the surface of sodium montmorillonite. The polymerization was carried out with γ-rays or benzoyl peroxide with or without crosslinking agent. Both insertion homopolymers and copolymers are associated in “packets” containing several macromolecules. The architecture of these aggregates is reminiscent of the elementary crystallite of montmorillonite. The aggregates can be dissociated irreversibly into individual macromolecules which display unusual light scattering and viscosity behavior. Only insertion homopolymers or copolymers prepared with benzoyl peroxide and without crosslinking agent follow the usual viscosity molecular weight relationship for linear (poly(methyl methacrylate). Insertion polymers or copolymers prepared with γ-rays display unusual viscosity and light scattering properties irrespectively of the presence of crosslinking agent. A compact two-dimensionally crosslinked architecture is compatible with the properties observed. This hypothesis is confirmed by the hydrodynamic properties of sodium salts of crosslinked insertion copolymers in methanol and in water. The polyelectrolytes appear to be extensively crosslinked and to display an oblate macromolecular conformation upon expansion.

Graft copolymers of acrylonitrile on unsaturated polyols

Abstract: GRAFT COPOLYMERS ARE PREPARED BY THE IN SITU POLYMERIZATION OF ACRYLONITRILE IN AN UNSATURATED POLYOL IN THE PRESENCE OF A FREE RADICAL CATALYST. THE COPOLYMERS ARE TRANSPARENT HOMOGENEOUS LIQUIDS WHICH MAY BE EMPLOYED IN THE PREPARATION OF FLEXIBLE URETHANE FOAMS HAVING SUPERIOR LOAD BEARING PROPERTIES.

Carboxylic acid latices providing unique thickening and dispersing agents

Abstract: A LATEX COMPOSITION COMPRISING A STABLE AQUEOUS DISPERSION OF A COPOLYMER PREPARED IN AN ACID AQUEOUS MEDIUM BY EMULSION POLYMERIZATION OF MONOMERIC MATERIAL CONTAINING FROM ABOUT 20% TO ABOUT 55% BY WEIGHT OF METHACRYLIC ACID, FROM ABOUT 3% TO ABOUT 35% BY WEIGHT OF AN ESTER OF AN ETHOXYLATED ALCOHOL, E.G., AN ESTER OF MALEIC ANHYDRIDE AND DINONYLPHEOXYPOLY(ETHYLENEOXY)ETHANOL, AND A BALANCE COMPRISING AT LEAST 35% BY WEIGHT OF STYRENE BUTADIENE OR MIXTURES THEREOF. THICKENING AGENTS HAVING EXCEPTIONAL THICKENING EFFCIENCY AND POLYMERIC EMULSIFIERS ARE PREPARED FROM THIS LATEX COMPOSITION BY ADJUSTING THE COMPOSITION TO AN ALKALINE PH.

Process of forming copolymers of maleic anhydride and an aliphatic olefin having at least 30 carbon atoms

Abstract: MALEIC ANHYDRIDE AND AN ALIPHATIC OLEFIN HAVING AT LEAST 30 CARBON ATOMS PER MOLECULE ARE COPOLYMERIZED IN THE PRESENCE OF A SOLVENT COMPRISING AN ALIPHATIC KETONE HAVING FROM 3 TO 5 CARBON ATOMS, SUCH AS METHYLETHYLKETONE, AND IN THE PRESENCE OF A FREE-RADICAL CATALYST USING A SUFFICIENT AMOUNT OF KETONE TO MAINTAIN NOT ONLY THE REACTANTS BUT ALSO THE COPOLYMER PRODUCTS IN SOLUTION. THE UNREACTED MONOMERS ARE PRECIPITATED FROM THE REACTION PRODUCT SOLUTION IN A FILTERABLE PARTICULATE SOLID FORM BY COOLING THE REACTION PRODUCT SOLUTION TO A TEMPERATURE LESS THAN THE CRYSTALLIZATION TEMPERATURE OF THE ALIPHATIC OLEFIN IN THE PRESENCE OF SUFFICIENT ADDITIONAL AMOUNTS OF KETONE SOLVENT, IF REQUIRED, TO MAINTAIN THE COPOLYMER IN SOLUTION AND PRECIPITATE THE OLEFIN MONOMER IN A FINELY DIVIDED FILTERABLE FORM. THE PRECIPITATED MONOMER CAN THEN BE SEPARATED FROM THE COPOLYMER SOLUTION BY ANY SUITABLE MEANS, SUCH AS FILTRATION.

Tough, stable tetrafluoroethylene-fluoroalkyl perfluorovinyl ether copolymers

Abstract: Tough, stable copolymers of tetrafluoroethylene monomer and fluorovinyl ether monomers can be produced by polymerizing the monomers in perfluorinated or suitable non-perfluorinated hydrogen and chlorine containing fluorocarbon solvents by a process that requires that the reaction be carried out at from about 30° to about 75° C. in the presence of a low temperature initiator such as bis(perfluoro propionyl) peroxide and a hydrogen containing chain transfer agent such as methanol.

Thermoplastic resin blend of polyphenylene oxide with butadiene-containing polymers

Abstract: BLENDS OF THERMOPLASTIC POLYPHENYLENE OXIDE RESIN (WHICH OPTIONALLY CONTAINS AN ALKENYL AROMATIC POLYMER SUCH AS A STYRENE POLYMER) WITH BUTADIENE HOMOPOLYMERS AND COPOLYMERS ARE CHARACTERIZED BY AN UNUSUALLY USEFUL COMBINATION OF PROPERTIES, PARTICULARLY LOW TEMPERATURE MELT PROCESSABILITY IN COMBINATION WITH HIGH IMPACT STRENGTH AND FLEXURAL STRENGTH.

Intramolecular Triplet Energy Transfer in Poly(1‐vinylnaphthalene)

Abstract: Poly(1‐vinylnaphthalene) in a rigid glass at 77°K exhibits a delayed fluorescence due to triplet–triplet annihilation following intramolecular triplet energy transfer through the naphthalene chromophores. Delayed fluorescence does not appear in the spectrum of 1‐ethylnaphthalene at equivalent concentrations, about 10−3M. Delayed emission from the polymer but not from 1‐ethylnaphthalene is quenched by piperylene. End groups are more important than chain length in the control of triplet migration in the homopolymer; experiments with 1‐vinylnaphthalene‐methyl methacrylate copolymers, however, indicate that some minimum chain length is required for efficient annihilation.

Solvent Effect in Radical Copolymerization of Methyl Methacrylate with Styrene

Abstract: A study of the copolymerization of methyl methacrylate and styrene in monosubstituted benzenes such as benzene, benzonitrile, benzyl alcohol, and phenol was made at 60°C. It was found that the copolymerization parameters changed significantly with the polarity of solvents, and the relative reactivity of methyl methacrylate toward the polystyryl radical was correlated with the ET values of solvents. These results and spectroscopic data suggest that in the transition state of this copolymerization the polarized structure of methyl methacrylate monomer became important, enhancing its reactivity, as the solvents became more protic.

Organic polymers containing siloxane-organic block copolymers

Abstract: A composition comprising (1) an organic polymeric material selected from the group consisting of polyolefins, polyethylene terephthalate, polyvinyl chloride, polyvinylidene chloride, polystyrene, polymethyl methacrylate, natural rubber, polyisoprene, butadiene-styrene copolymer, chloroprene polymers, isobutylene polymers, acrylic resins, epoxy resins, polyamides, butadiene-acrylonitrile copolymers, melamine-formaldehyde resins, phenol-formaldehyde resins, and urea-formaldehyde resins; and (2) from 0.001 to 10 percent by weight based on the weight of said organic polymeric material of a linear block copolymer comprising at least one organosiloxane block (A) containing at least 20 units of the formula R2SiO- wherein each R is selected from the group consisting of hydrogen atoms, monovalent hydrocarbon radicals, monovalent halogen-substituted hydrocarbon radicals and amino alkyl radicals and at least some of the R groups in said organosiloxane block are not hydrogen; and an organic block (B) selected from the group consisting of polymers formed by the polymerization of at least one compound selected from the group consisting of methyl methacrylate, styrene, chlorostyrene, alpha methyl styrene, vinyl chloride, vinyl pyridine, acrylonitrile, butadiene, isoprene, epsilon-caprolactum, and olefins, said organic block being at least partially compatible with said organic polymeric material; and said linear block copolymer being of the type BAB or of the type AB wherein B represents said organic block and A represents said organosiloxane block.

Copolymerization of butadiene and styrene by initiation with alkyllithium and alkali metal tert‐butoxides

Abstract: Combinations of the various alkali metal tert-butoxides with organolithium initiators give homogeneous copolymers of butadiene and styrene. The unprecedented flexibility of this initiator system allowed preparation of random copolymers with various amounts of vinyl unsaturation and various degrees of randomness. The butyllithium–potassium tert-butoxide initiator system was more efficient than phenylpotassium.

Method of producing betaines, monomers and polymers containing betaine-type units and novel and useful copolymers thereby obtained

Abstract: An improved method is provided for producing polymers of organic compounds, such as ethylenically unsaturated monomers, containing a betaine-type group of the formula: ##STR1## The method involves the reaction of acrylic acid or aqueous methyl acrylate and an aminoalkyl (meth)acrylate or an N-amino-alkyl (meth)acrylamide having a basic tertiary nitrogen atom in the presence of a free radical initiator. The monomers undergo vinyl addition polymerization to form valuable polymers having a wide variety of uses, such as flocculants, retention aids in the deposition of polymers, pigments, etc. on the fibers in a paper pulp, e.g., in the formation of mineral-filled papers.

Alternating copolymerization of polar vinyl monomers in the presence of zinc chloride. I. Propagation and initiation of the copolymerization of acrylonitrile with styrene copolymer

Abstract: Copolymerization of acrylonitrile with styrene spontaneously occurred on addition of zinc chloride without addition of any other radical initiator. The composition of the copolymer approached that of strictly alternating copolymer as zinc chloride added to the copolymerization system increased. The significance of the apparent monomer reactivity ratios of this copolymerization system was studied from a kinetic point of view, and it was shown that the monomer sequence distribution is indicated by the apparent monomer reactivity ratios. Further, equations which represent the relation between the apparent monomer reactivity ratios and Q,e values at a given salt concentration were derived. These equations reasonably accounted for the decrease of the apparent monomer reactivity ratios of the copolymerization of acrylonitrile with styrene in the presence of zinc chloride and the behavior of the other acrylonitrile copolymerization systems in the presence of zinc chloride. The initiation step of the spontaneous radical copolymerization of acrylonitrile with styrene in the presence of zinc chloride was explained by a cross-initiation mechanism.

Effects of metal salts on polymerization. Part VII. Radical polymerization and spectra of vinylpyridine in the presence of cobaltous chloride

Abstract: The radical polymerizability of vinylpyridines in the presence of cobaltous chloride was studied in DMF solution, and the results were correlated with the spectroscopic data obtained for methanol solution. In general, the behavior of vinylpyridine complexed with cobaltous chloride is qualitatively the same as that of zinc complexes reported previously. The rates of polymerization were enhanced by the addition of cobaltous chloride when 4-vinylpyridine(4-VP) or 2-methyl-5-vinylpyridine(MVP) was the monomer, whereas the polymerization of 2-vinylpyridine(2-VP) was retarded by cobaltous chloride. The monomer reactivity of all the vinylpyridines was also enhanced by complex formation as studied by copolymerization with styrene. The enhancement of reactivity of 4-VP complexed with cobaltous chloride is somewhat smaller than that of the corresponding zinc complex.

Production of rubber-modified vinylaromatic polymers

Abstract: PROCESS FOR THE PRODUCTION OF IMPACT-RESISTANT POLYMERS BY THE CONTINUOUS POLYMERIZATION OF A SOLUTION OF A DIENE ELASTOMER OR ELASTOMERIC COPOLYMER OF ETHYLENE AND PROPYLENE, THE STARTING MATERIALS BEING FIRST PARTIALLY POLYMERIZED TO SUCH AN EXTENT THAT THE SOLIDS CONTENT OF THE MIXTURE IS 1.1 TO 2 TIMES THE CONTENT OF DIENE ELASTOMER BUT NOT MORE THAN 16% BY WEIGHT, THEN INTRODUCED INTO AN ISOTHERMAL POLYMERIZATION STAGE WHERE A MIXTURE CONTAINING LESS THAN 50% BY WEIGHT OF SOLIDS IS PREPARED AT A TEMPERATURE OF FROM 50* TO 150*C. WHILE MIXING, WHICH MIXTURE IS TOTALLY POLYMERIZED IN THE DOWNSTREAM CONTINUOUS POLYMERIZATION STAGES AT A TEMPERATURE OF UP TO 250*C. TO GIVE A MIXTURE CONTAINING MORE THAN 60% BY WEIGHT OF SOLIDS, AND THEN FREED IN A CONVENTIONAL MANNER FROM VOLATILE CONSTITUENTS.

Radiation curable acrylic urethane monomers

Abstract: A radiation curable composition is provided by reacting about one mole of an organic diisocyanate with about one mole of a hydroxyacrylate to form a mono-urethane adduct which is subsequently reacted with a styrene-allyl alcohol copolymer having a molecular weight between about 200 and 30,000, the reaction product being essentially free of unreacted isocyanate groups.

Process for producing copolymer of epoxide and carbon dioxide

Abstract: A PROCESS FOR PRODUCING HIGH MOLECULAR WEIGHT COPOLYMERS OF AN EPOXIDE, SUCH AS PROPYLENE OXIDE, ETHYLENE OXIDE, STYRENE OXIDE, ISOBUTYLENE OXIDE OR EPICHLOROHYDRIN, AND CARBON DIOXIDE, WHEREIN THE COPOLYMERIZATION REACTION OCCURS UNDER THE PRESSURE OF CARBON DIOXIDE GAS AND IN THE PRESENCE OF AN ORGANOMETALLIC COMPOUND AS A CATALYST.

Graft copolymers of styrene acrylonitrile and methyl acrylate onto diene polymers and blends thereof with vinyl chloride resins

Abstract: A GRAFT POLYMER AND A METHOD OF PREPARING THE GRAFT POLYMER, WHICH POLYMER IS SUTIABLE FOR BLENDING WITH POLY (VINYLCHLORIDE) TO PROVIDE A TRANSPARENT COMPOSITION THAT EXHIBITS TRANSPARENCY AND AN OPTIMUM BALANCE OF PHYSICAL PROPERTIES. THE GRAFT POLYMER IS PREPARED BY POLYMERIZING SYYRENE, ARCYLONITRILE AND METHYL ACRYLATE IN THE PRESENCE OF A DIENE RUBBER SUBSTRATE.

Quantitative study of the annealing of poly(vinyl chloride) near the glass transition

Abstract: Poly(vinyl chloride) displays a normal DSC or DTA curve for the glass transition when quenched from above its T g . However if cooled slowly or annealed near the glass-transition temperature, a peak appears on the DSC or DTA curve at the T g . In this article quantitative studies of the time and temperature effects on the production of this endothermal peak during the annealing of PVC homopolymer and an acetate copolymer are presented. This phenomenon conforms to the Williams, Landell, and Ferry equation for the relaxation of polymer chains, the rate of the peak formation becoming negligible at more than 50°C below T g . The energy difference between the quenched and annealed forms is small. For a PVC homopolymer annealed 2 hr at 68°C, which is T g -10°C, the difference is 0.25 cal/g. For a 13per thousand acetate copolymer of PVC similarly annealed, the difference is 0. 36 cal/g. The measured rates of the process give a calculated activation energy of 13-14 kcal/mole for PVC homopolymer and copolymer. This appearance of a peak on the T* lg*s curve for a polymer when annealed near the glass temperature appears to be a general phenomenon.

Tire having polyurethane laminate thereon

Abstract: A tire and method of preparation which comprises a cured rubber tire having adhered thereto a laminate of a cured polyurethane comprising a cured reaction mixture prepared by reacting an organic polyisocyanate with a reactive hydrogen containing material having a molecular weight of from about 700 to about 5,000 and a hydroxyl functionality of greater than 2.0 up to about 3,0 selected from hydroxyl terminated polymers of the group consisting of polymers and copolymers of 1,3-diene hydrocarbons having 4 to 6 carbon atoms, copolymers of 1,3-diene hydrocarbons having 4 to 6 carbon atoms with styrene, acrylonitrile, ethyl acrylate and chlorosubstituted 1,3-diene hydrocarbons having 4 to 6 carbon atoms.