The invention provides a polyamide resin composition (1) containing a polyamide (A) and a free volume modifier (B), and having a free volume, as measured according to a positron annihilation method, of 0.0545 nm.sup.3 or less. The invention also provides a polyamide resin composition (2) prepared by adding from 0.005 to 1.200 parts by mass of a polysilsesquioxane (B) whose main chain is comprised of siloxane bonds, to 100 parts by mass of a polyamide (A) that contains a diamine unit including an aromatic diamine unit represented by the following general formula (I) in an amount of 70 mol % or more and a dicarboxylic acid unit including at least one of a linear aliphatic dicarboxylic acid unit represented by the following general formula (II-1) and an aromatic dicarboxylic acid unit represented by the following general formula (II-2) in a total amount of 50 mol % or more: ##STR00001##
wherein n in the general formula (II-1) indicates an integer of from 2 to 18, and Ar in the general formula (II-2) represents an arylene group.

An improved process for forming polyamide dispersions in water utilizing carbon dioxide to facilitate dispersion of the polyamide is disclosed. The polyamides are generally below 30,000 or 40,000 g/mole molecular weight when dispersed, but can be chain extended with polyfunctional species such as polyisocyanates after dispersion. The dispersions are useful in coatings, adhesives, and inks. Composites and hybrids of these other polyamides with vinyl polymers are also disclosed and claimed.

Disclosed herein is a method to recover constituent polymers in multilayer plastic films or mixed plastic wastes. The method comprises selectively dissolving a polymer in a solvent at a temperature, wherein the polymer is soluble, but other polymers in the multilayer plastic film or mixed plastic waste are not. The solubilized polymer is then separated from the multilayer plastic film or mixed plastic waste by mechanical filtration and precipitated by changing the temperature and/or adding a cosolvent. The process is repeated for each of the polymer component, resulting in a number of segregated streams that can then be recycled. Computational tools can be used to select solvent systems and temperatures that selectively dissolve different polymers from among all of the components.

The present invention provides a polyamide composite material, which includes the following components in parts by weight: 25-85 parts of a polyamide resin; 10-50 parts of a glass fiber; 5-25 parts of polytetrafluoroethylene; and 0.1-2 parts of at least one of a K/Na/Ca/Mg/Ba/Zn/Li/Al salt of montanic acid. The montanate can effectively inhibit free hydrogen fluoride in the polytetrafluoroethylene, thereby effectively inhibiting free silicon in the glass fiber and improving the electrical performance of the material.

A method of manufacturing a coextruded and/or laminated and biaxially oriented composite film and a resulting multilayered film which has improved processability and/or improved recyclability. For this purpose, the method and multilayered film provides a novel combination of the density of various layer components of the composite film and certain manufacturing parameters such as the stretching factors, relaxation factors, relaxation temperatures, and residual stretching factors.

A water soluble polymer blend composition includes at least one water soluble polymer and at least one immiscible polymer. The water soluble polymer and the immiscible polymer can be melt processed at a temperature above their respective melt processing temperatures and quenched to form the water soluble polymer blend composition in a non-equilibrium state, such that it can exhibit a non-equilibrium morphology. Non-equilibrium morphologies can include, e.g., a microfiber morphology or a co-continuous morphology.

The present invention relates to a polymer film comprising a base film comprising polyamide-based resin; and two or more kinds of copolymers comprising polyamide-based segments and polyether-based segments, and a method for preparing the polymer film.

A laminated film having a resin layer laminated on at least one surface of a base film. The laminated film is characterized by: the base film being a semi-aromatic polyamide film that has been at least uniaxially stretched; the resin layer having a thickness of 0.03 to 0.5 μm; and the close adhesion between the base film and the resin layer, according to the cross-cut method described in JIS K 5600, being 95% or more.

A polyamide resin, according to the present invention, is formed through polycondensation of a monomer comprising 1,4-cyclohexanedicarboxylic acid, 1,10-decanediamine, and 1,12-dodecanediamine, wherein the molar ratio of 1,10-decanediamine and 1,12-dodecanediamine is approximately 10:90 to approximately 65:35. As a result, the polyamide resin capable of enabling high durability and color stability in the polyamide molded body can be provided.

A polymer powder having a surface energy of less than 35 mN/m is suitable for melting/sintering powder particles for layer-by-layer production of three-dimensional objects.