Showing papers on "Styrene-butadiene published in 1994"

Recyclable and compostable coated paper stocks and related methods of manufacture

Abstract: Recyclable and compostable coated paper stock comprising a substrate coated on at least one surface with a primer coat and a top coat both of which are water based dispersions. The primer coat comprises a water based dispersion of a polymer selected from the group comprising acrylic polymers, acrylic copolymers, polyvinyl acetate, polyvinyl alcohol, poly-ethylene vinyl acetate, poly-ethylene vinyl chloride, styrene butadiene copolymers, polyvinylidiene chloride or starch. The top coat comprises a water based dispersion of a polymer selected from the group comprising acrylic polymers, acrylic copolymers, styrene butadiene copolymers or polyvinylidiene chloride. In another embodiment the top coat further includes a wax component comprising 15-90 wt. % of the polymer and 5-85 wt. % of the wax. The substrate is coated with a primer coat prior to the application of the top coat to seal the substrate surface. The top coat forms a film over the primer coat and imparts water and grease resistant properties to the coated paper stocks. The invention also includes processes for making and using the invented coated paper stocks.

Method for Estimating the Chemical Crosslink Densities of Cured Natural Rubber and Styrene-Butadiene Rubber

Abstract: Chemical crosslink densities of gum and carbon black-filled natural rubber (NR) and styrene-butadiene rubber (SBR) were estimated by using a newly developed rheometer. The rheometer is the Rubber Process Analyzer (RPA 2000) which is designed specifically to measure dynamic properties such as shear storage modulus G′ and shear loss modulus G″ in cured and uncured rubber. It was found that the differences between the G′ values of dicumyl peroxide-cured NR and those of uncured samples yielded estimates of the crosslink densities which were nearly the same as the values inferred by chemical analysis. For TMTD-cured SBR, the same procedure yielded estimates of chemical crosslinks very close to those estimated by a tensile stress-strain method and by NMR. In addition, accelerated sulfur-cured natural rubber was also investigated. The agreement between the crosslink densities of these stocks determined from G′ values and from a solvent-swelling method was very good.

Fast processing water based binder system

Abstract: The invention relates to a water based binder for use in a slurry for investment casting. The binder includes a mixture of a colloidal silica sol and at least one latex polymer. The latex polymer is preferably an acrylic latex or a styrene butadiene polymer (or a combination of these) which reduces the processing time between dips during shell mold making for investment casting. The latex polymer further lowers a critical concentration point or gelation point of the colloidal silica sol. The binder may be used as a primary binder or a backup binder in the shell mold making process. To make the slurry, the binder is combined with at least one refractory powder, preferably a refractory powder selected from the group of: alumino-silicates, fused silica, quartz silica, alumina, zircon, and zirconia.

The Preparation, Properties and Potential Applications of “Diimide-Hydrogenated” Styrene-Butadiene (HSBR) and Polybutadiene (HBR) Thermoplastic Elastomers

Abstract: Our unique diimide-based process for preparing HNBR latex from NDR latex without the use of hydrogen, noble metal catalysts or solvents has now been successfully extended to the preparation of hydrogenated thermoplastic elastomers latexes directly from SBR or BR latex precusors. Commercially available SBR latex such as SBR 1502 can be readily reduced to high saturation levels (95+%) via the diimide reduction technique. Latex cast films of the highly reduced elastomer show excellent ozone and oxidation resistance as expected. Unexpectedly however, the hydrogenated polymer films demonstrate high tensile strength and thermoplastic elastomer (TPE) behavior. The TPE properties have been found to be caused by polyethylene crystallites that exist even in the unstretched films under ambient conditions. Latex is an unusual physical form for a TPE material. As a latex, TPE elastomers can be fabricated into sheets or other products by simple dipping or spraying methods—methods not normally available to TPEs...

High-solids adhesives and method of producing same

Abstract: A method of producing a high solids adhesive is provided wherein a buffered latex emulsion, such as, for example, styrene butadiene latex emulsion buffered to a pH of 11.0 using caustic agents, is combined with a non-emulsified mixture of dissolving process oils and tackifying resins and mineral fillers. The resultant adhesive has a solids content greater than previously achieved in the industry and has exceptional adhesive characteristics such as increased bond strength, improved durability, better aging, faster drying, improved water resistance and improved freeze resistance. High solids content is achieved by taking advantage of the excess emulsifiers in the latex emulsion and adding the remaining constituent components directly to the stabilized latex emulsion.

Miscibility, Microstructure, and Dynamics of Blends Containing Block Copolymer. 2. Microstructure of Blends of Homopolystyrene with Styrene-Butadiene Block Copolymers

Abstract: The microstructures of styrene-butadiene triblock (SBS) and styrene-butadiene four-arm star block (SB-4A) copolymers and their blends with homopolystyrene (PS) of different molecular weights, MPS, have been investigated by means of small-angle X-ray scatt

Comparison of the Effect of a Hydrocarbon Oil and a Terpene Tackifier on the Autohesion of Styrene-Butadiene Rubber

Abstract: Blends of uncrosslinked styrene-butadiene rubber (SBR) with a terpene tackifier resin or a naphthenic oil have been characterized, and their autohesion and cohesion determined using a T-peel geometry. SBR/oil blends are homogeneous at all proportions, while SBR/resin blends, based on DSC and DMA analysis, undergo bulk phase separation at about 50% resin. However, migration of tackifier to the surface region is proposed at much lower resin contents. Compositions diluted with oil have autohesion similar to the neat SBR. This is attributed to compensating effects; although oil hastens self-bond formation by increasing chain mobility, this is nearly equally balanced by more facile chain separation during bond rupture. In short, oil-diluted compositions are soft and weak. On the other hand, SBR compositions containing small amounts of resin have high autohesion. Resin-diluted specimens deform easily at low strain, just as those containing oil, but intertwined chains of the former have greater resistan...

Use of silane coupling agent with carbon black to enhance the balance of reinforcement properties of rubber compounds

Abstract: A method of improving balance of properties, such as increased reinforcement and reduced rolling resistance of a rubber compound, comprising mixing the rubber compound with a carbon black and a silane coupling agent for a period of between about 10 seconds and 20 minutes at a temperature of between about 160° C and 180° C such as a styrene butadiene rubber compound, is disclosed The method involves mixing the rubber compound "in situ" with a carbon black and Bis(3-triethoxysilylpropyl)-tetrasulfane at ambient temperature

Investigation of the molecular transport of aliphatic and aromatic esters into engineering polymer membranes

Abstract: Molecular transport as manifested by sorption and diffusion of organic esters into engineering polymer membranes, viz. nitrile butadiene rubber, styrene butadiene rubber, ethylene propylene diene terpolymer, neoprene and natural rubber, has been investigated in the temperature range 25–60°C by the sorption gravimetric technique. The sorption equilibrium for ethylene propylene diene terpolymer was lower than those of the other polymers with all the liquids. Diffusion and permeation coefficients were obtained for the polymer-solvent systems and these follow Arrhenius type behaviour in the temperature range investigated.

Hydrogenation of styrene-butadiene rubber by hydrogen transfer from limonene

Abstract: The heterogeneous catalytic transfer hydrogenation of styrenebutadiene rubber (SBR) by the use of limonene as hydrogen source and as solvent in the presence of Pd/C as catalyst has been studied. The influence of the heating time on the reduction and on the structure of the donor was studied. Partial hydrogenations of the olefinic bonds of SBR are obtained when a mixture of limonene, SBR and 10% Pd/C is refluxed with vigorous stirring for 50–200 minutes.

Super wearproof rubber liner for cold burden and its production method

Abstract: The antiwear rubber liner instead of metallic one is prepared from natural rubber, styrene butadiene rubber, cis-butadiene rubber, activator, accelerator, softening agent, aging agent, vulcanizator, plasticizer, strengthening agent and filler and features low self load, high antiwear nature, long service life and low cost.

Miscibility, Microstructure, and Dynamics of Blends Containing Block Copolymer. 3. Molecular Motion in Homopolystyrene and Polystyrene/Four-Arm Styrene-Butadiene Star Block Copolymer Blends

Abstract: The proton spin-spin relaxation times (T-2(H)) at different temperatures (from 160 to 390 K) have been determined for polystyrene (PS) and four-arm star styrene-butadiene block copolymer (SB-4A) and its blends with PS of different molecular weights (M(PS)

Ground cover sheet formed of varible biodegradable cellulosic fiber composition and method of making same

Abstract: A biodegradable ground cover sheet formed from a mulch which comprised of cellulosic fibers in the amount of 25-95% and in admixture with 0-40% residual sludge from a paper making process and 0-40% peat moss. Additives are also added to the mixture in the amounts of 0-25% and these are formed from a mixture of ingredients including styrene butadiene base latex and cellophane or colophane. A mineral compound in the amount of 0-50% is also added to the mixture and is selected from clay, calcium carbonate or talc. A predetermined quantity of selected biodegradable additives are also added. The mixture has a preselected quantity of the above-mentioned compounds depending on its intended use and desired biodegradable time. The sheet outer surfaces may also be coated with a wax to adjust the biodegradable time.

Coin type nonelectrolytic secondary battery

Abstract: PURPOSE: To improve charge and discharge cycle property, shelf life, and drop property by using a mixture between rubber high molecules and cellulose having liquid preservation property as the binding agent of a coupling agent of negative electrode. CONSTITUTION: The swelling of a negative pole coupling agent is reduced by adding and mixing the mixture between a rubber high molecule, as a binding agent, and cellulose ether having liquid preservation property into carbonic powder, and forming it into a pellet shape, and also an electrolyte can be preserved by a proper amount. And, as a rubber high polymer, methacrylic acid alkyl ether butadiene copolymer, styrene butadiene rubber, or the like is used, and as cellulose having liquid preserving property, carboxymethyl cellulose sodium, methyl hydroxyethyl cellulose, etc., is used. By using the mixture between rubber high polymer and cellulose ether as the binding agent of a negative electrode coupling agent, excellent charge and discharge property, storage property, and fall property can be materialized. COPYRIGHT: (C)1995,JPO

Effect of styrene content and ZnO-stearic acid on the mechanical properties of radiation-vulcanized styrene-butadiene rubber (SBR)

Abstract: The effect of styrene content on the properties of electron irradiation-vulcanized SBR loaded with carbon black was pronounced only at low irradiation doses where the crosslinking densities were not so high. At high doses, no effect was observed especially for SBR containing ZnO. It was also observed that ZnO (3 phr) increased the tensile strength of SBR containing 23.5 wt.-% styrene by 20% at 20 kGy irradiation dose, compared to 5% at higher doses for SBR containing 46 wt.-% styrene. However, the increase in tensile strength by ZnO for loaded SBR (23.5%) was almost 17% at all irradiation doses. Besides, tear strength, abrasion resistance and elongation at break were remarkably improved. The high efficiency of ZnO toward SBR (23.5%) may be attributed to the higher butadiene content. The behavior of SBR (46%) at 20 kGy was surprising, since both tensile strength and elongation at break were almost maximum. Der Einflus des Styrolgehalts auf die Eigenschaften von elektronenstrahlvernetztem, rusgefulltem Styrol-Butadien-Kautschuk (SBR) war nur bei niedrigen Strahlungsdosen, d. h. geringen Vernetzungsgraden, ausgepragt. Bei hohen Dosen wurde kein Effekt beobachtet, insbesondere fur ZnO-enthaltenden SBR. Es wurde auserdem festgestellt, das ZnO (3 phr) die Zugfestigkeit von SBR mit einem Styrolgehalt von 23,5 Gew.-% bei 20 kGy um 20% verbesserte, verglichen mit SBR mit 46 Gew.-% Styrol. Die Zunahme der Zugfestigkeit fur gefullten SBR (23,5%) betrug bei allen Strahlungsdosen nahezu 17%. Daneben waren Reisfestigkeit, Abrasionswiderstand und Bruchdehnung erheblich verbessert. Die hohe Effizienz von ZnO bei SBR (23,5%) konnte auf dessen hoheren Butadiengehalt zuruckzufuhren sein. Das mechanische Verhalten von SBR (46%) bei 20 kGy war uberraschend, da sowohl Zugfestigkeit als auch Bruchdehnung nahezu maximal waren.

The Effect of the Environment on the Friction and Wear of Blended Rubber

Abstract: The friction and wear of rubber are properties that are affected by the environment, especially by the oxygen in the air. Natural rubber (NR) is most sensitive to air, butadiene rubber (BR) is scarcely affected by the presence of air, while styrene butadiene rubber (SBR) is intermediate compared to NR and BR. Both the abrasive and fatigue wear rates of NR and BR blends are known to decrease by increasing the BR content. To reduce the wear rates of NR vulcanizates in the air, SBR was blended with NR. In severe rubbing experiments against abrasive cloths, the wear rate of the NR‐SBR blends slightly decreased by increasing the SBR content. The NR‐SBR blends showed considerable reduction in wear under fatigue wear conditions against metal gauze. Similar experiments were also conducted for SBR‐BR blends. Blending with BR showed a substantial reduction in wear, especially in fatigue wear. When NR‐BR, NR‐SBR, and SBR‐BR blends were rubbed against metal gauze in vacuum, the friction and wear of these thr...

Oil resistant pick-up belt and swather canvas

Abstract: An improved crop harvesting belt for swather belt and pick-up belt applications, which is both oil resistant and cold weather reliable, the belt made of a compound of styrene butadiene rubber and nitrile rubber, the nitrile rubber preferably at approximately 6% of the compound and having an acrylonitrile level of approximately 33% by weight.

Physico-Mechanical Properties of Styrene-Butadiene Rubber (SBR) Filled with Egyptian Kaolin

Abstract: Styrene butadiene rubber formulations utilizing Egyptian Kaolin as a filler, were evaluated against a commercial imported Kaolin sample.

Styrene/butadiene toner resins with excellent gloss and fix properties

Abstract: A toner composition includes a styrene/butadiene resin having a weight average molecular weight of less than about 70,000 and a number average molecular weight of from about 8,000 to about 12,000, has a glass transition temperature of from about 50° C. to about 60° C. and provides excellent gloss and high fix properties at a low fusing temperature. The styrene/butadiene resin is produced by an emulsion polymerization process that includes forming an emulsion of a surfactant, styrene monomer, butadiene monomer and a water-soluble monomer in water, and then polymerizing the monomers in the presence of a water-soluble initiator.

Ion-free latex films as dual-phase electrolytes : styrene-butadiene rubber and nitrile-butadiene rubber synthesized by emulsion polymerization with poly(vinyl pyrrolidone) stabilizer

Abstract: Ion-free latices of styrene-butadiene rubber (SBR) and nitrile-butadiene rubber (NBR) were synthesized by emulsion polymerization with use of poly(vinyl pyrrolidone) (PVP) stabilizer. The goal was to prepare ion-free latex films, possessing dual-phase latex particle morphology, and swell the films with liquid electrolyte to yield dual-phase polymer electrolytes (DPE). SBR/PVP latex was prepared readily, but NBR/PVP latex was sensitive to coagulation. DSC and SEM analyses of latex films provided morphological evidence concerning particle structure and phase separation

Process for producing modified water-proof thick asphalt paint

Abstract: The water-proof modified asphalt paint for roof and underground structure is prepared through mixing styrene butadiene latex with emulsified liquid and heating while adding hot asphalt for emulsifying sufficiently. Emulsifier (bentone and asbestos), emulsifying assistant, pH value regulator and stabilizer are also used. It features low cost and excellent film-forming nature.