1881 results about "Melt viscosity" patented technology

Main chain thermotropic liquid crystal esters, ester-imides, and ester-amides were prepared from AA, BB, and AB type monomeric materials and were end-capped with phenylacetylene, phenylmaleimide, or nadimide reactive end-groups. The resulting reactive end-capped liquid crystal oligomers exhibit a variety of improved and preferred physical properties. The end-capped liquid crystal oligomers are thermotropic and have, preferably, molecular weights in the range of approximately 1000-15,000 grams per mole. The end-capped liquid crystal oligomers have broad liquid crystalline melting ranges and exhibit high melt stability and very low melt viscosities at accessible temperatures. The end-capped liquid crystal oligomers are stable for up to an hour in the melt phase. These properties make the end-capped liquid crystal oligomers highly processable by a variety of melt process shape forming and blending techniques including film extrusion, fiber spinning, reactive injection molding (RIM), resin transfer molding (RTM), resin film injection (RFI), powder molding, pultrusion, injection molding, blow molding, plasma spraying and thermo-forming. Once processed and shaped, the end-capped liquid crystal oligomers were heated to further polymerize and form liquid crystalline thermosets (LCT). The fully cured products are rubbers above their glass transition temperatures. The resulting thermosets display many properties that are superior to their non-end-capped high molecular weight analogs.

This invention relates to a blend of biodegradable polymers comprising:(A) about 5% to about 95% by weight of at least one flexible biodegradable polymer (A) having a glass transition less than about 0° C.,(B) about 5% to about 95% by weight of at least one rigid biodegradable polymer (B) having a glass transition greater than about 10° C., and(C) about 0.25 to about 10 weight % of at least one compatibilizer (C), said percentages being based on the total weight of the polymer blend;where the polymer blend has a higher zero shear melt viscosity than polymers (A) and (B) separately.

A molding composition of at least 50% by weight of a polyamine-polyamide copolymer obtained from 0.05 to 2.5% by weight of a polyamine having at least 4 nitrogen atoms and having a viscosity of at least 5 000 Pa.s at 250° C. and at a shear rate of 0.1 l / s, and having a viscosity ratio of at least 7 at 250° C., when the melt viscosities at shear rates of 0.1 l / s and 100 l / s are compared with one another, has high melt stiffness and is easy to cut, and performs well in blow molding.

A thermoplastic elastomer composition dynamically vulcanized to a gelation rate of 50 to 95% which is superior in heat resistance and durability while maintaining flexibility and superior in air permeation preventive property which can be efficiently used as, for example, a pneumatic tire as an air permeation preventive layer. In particular, a thermoplastic elastomer composition having a reduced particle size of the domain rubber is produced by a material having a high rubber ratio by mixing a composition (C) mixed under conditions of a ratio of melt viscosities of the rubber composition (A) / resin (B) of 0.8 to 1.2 and the formula (phiA / phiB)x(etaB / etaA)<1.0 under conditions of a ratio of melt viscosities of the rubber composition (D) / composition (C) of 0.8 to 1.2 and the formula (phiD / phiC)x(etaC / etaD)<1.0, wherein phiA: volume fraction of rubber composition (A), phiB: volume fraction of resin (B), etaA: melt viscosity of rubber composition (A), etaB: melt viscosity of resin (B), phiC: volume fraction of composition (C), phiD: volume fraction of rubber composition (D), etaC: melt viscosity of composition (C), etaD: melt viscosity of rubber composition (D).

A thermoplastic cellulose derivative composition of the present invention contains, as a main component, a cellulose ester having an aliphatic polyester side chain having a repeat unit having 2 to 5 carbon atoms, wherein a rate of heating loss at 200° C. is 5 wt % or less, a melt viscosity at 200° C. and 1000 sec−1 is 50 to 300 Pa·sec, and a melt tension at the time of take-up at 200° C. and 100 m / min is 0.1 to 40 mN. The present invention can provide excellent fiber products by melt spinning of the composition.

In the production method of polyamide of the present invention, the mole balance at a set point during melt polymerization is estimated from a pre-established equation for calculating the mole balance during melt polymerization from a melt viscosity. On the basis of the estimated mole balance, the subsequent conditions of melt polymerization of a batch and the polymerization conditions of the next and subsequent batches are determined. In addition, the mole balance, molecular weight and relative viscosity of melt-polymerized polyamide are estimated from pre-established equations each for respectively calculating the mole balance, molecular weight and relative viscosity at the end point of melt polymerization from the melt viscosity. The conditions for solid phase-polymerizing the melt-polymerized polyamide are determined on the basis of estimated values.

Polyimide copolymers were obtained containing 1,3-bis(3-aminophenoxy)benzene (APB) and other diamines and dianhydrides and terminating with the appropriate amount of reactive endcapper. The reactive endcappers studied include but should not be limited to 4-phenylethynyl phthalic anhydride (PEPA), 3-aminophenoxy-4'-phenylethynylbenzophenone (3-APEB), maleic anhydride (MA) and nadic anhydride (5-norbornene-2,3-dicarboxylic anhydride, NA). Homopolymers containing only other diamines and dianhydrides which are not processable under conditions described previously can be made processable by incorporating various amounts of APB, depending on the chemical structures of the diamines and dianhydrides used. By simply changing the ratio of APB to the other diamine in the polyimide backbone, a material with a unique combination of solubility, Tg, Tm, melt viscosity, toughness and elevated temperature mechanical properties can be prepared. The copolymers that result from using APB to enhance processability have a unique combination of properties that include low pressure processing (200 psi and below), long term melt stability (several hours at 300° C. for the phenylethynyl terminated polymers), high toughness, improved solvent resistance, improved adhesive properties, and improved composite mechanical properties. These copolyimides are eminently suitable as adhesives, composite matrices, moldings, films and coatings.

Disclosed is a new method and compositions from the method consisting of block copolycarbonate / phosphonates that exhibit an excellent combination of flame resistance, hydrolytic stability, high Tg, low melt viscosity, low color and high toughness. Also disclosed are polymer mixtures or blends comprised of these block copolycarbonate / phosphonate compositions and commodity and engineering plastics and articles produced therefrom. Further disclosed are articles of manufacture produced from these materials, such as fibers, films, coated substrates, moldings, foams, adhesives and fiber-reinforced articles, or any combination thereof.