12 results about "Inherent viscosity" patented technology

The invention relates to a process for recycling a particulate semi-crystalline polyamide, the initial particulate semi-crystalline polyamide having already been used in a layer-by-layer printing process, the process comprising: - a step of contacting the initial particulate semi-crystalline polyamide with water and at least one acid; - a step of heating the initial particulate semi-crystalline polyamide to a temperature above Tc – 20°C and below Tf, Tc denoting the crystallization temperature of the initial particulate semi-crystalline polyamide and Tf being the melting temperature of the initial particulate semi-crystalline polyamide, and - a step of collecting the treated particulate semi-crystalline polyamide, in which the treated particulate semi-crystalline polyamide has an inherent viscosity lower than the inherent viscosity of the initial particulate semi-crystalline polyamide.

A temperature-resistant polymer composition comprising: a. poly-2,5-benzimidazole having an inherent viscosity (IV) between 1.0 dL / g and 2.5 dL / g; and b. at least one binder having a glass transition temperature lower than that of the poly-2,5-benzimidazole and having an inherent viscosity in the range of 0.2 dL / g and 1.5 dL / g, which is subjected to compression at a temperature in the range of 400 °C to 600 °C and a pressure in the range of 689,475.72 Pa (1000 psi) to 689,475.29 Pa (10000 psi), wherein the composition is characterized by: i. a glass transition temperature in the range of 150 to 480 °C; and ii. a ratio of poly-2,5-benzimidazole to binder in a range between 95:5 and 5:95.

The invention relates to a method for recycling a particulate semicrystalline polyamide, wherein the initial particulate semicrystalline polyamide has already been used in a layer-by-layer printing process, the method comprising: a step of bringing the initial particulate semicrystalline polyamide into contact with water and at least one acid, a step of heating the initial particulate semicrystalline polyamide to a temperature higher than Tc - 20°C and lower than Tm, Tc denoting the crystallization temperature of the initial particulate semicrystalline polyamide and Tm being the melting temperature of the initial particulate semicrystalline polyamide, and a step of collecting the treated particulate semicrystalline polyamide, wherein the treated particulate semicrystalline polyamide has an inherent viscosity lower than the inherent viscosity of the initial particulate semicrystalline polyamide.

The invention relates to a seeded particle of polyamide (PA) powder consisting of:a polyamide core with a D50 within the range from 15 to 60 μm, anda polyamide shell,characterized in that the shell has an inherent viscosity in solution and a melting temperature which are respectively higher than those of the core.

The invention discloses a UV (ultraviolet) curing hot-melt pressure-sensitive adhesive with high cohesive strength. The UV curing hot-melt pressure-sensitive adhesive comprises butyl acrylate, 2-ethylhexyl acrylate, acrylic acid, a benzophenone derivative containing carbon-carbon double bonds, a solvent, an initiator BPO (benzoyl peroxide) and a nitroxide free radical TEMPO. Butyl acrylate and 2-ethylhexyl acrylate are used as main monomers, acrylic acid is used as a functional monomer, the inherent viscosity characteristic of an acrylic pressure-sensitive adhesive is reserved, the initial binding force with a base material is ensured, and a benzophenone derivative containing carbon-carbon double bonds has the dual functions of photo-initiation activity and cross-linking reaction point positions and can be copolymerized with the monomers to realize UV cross-linking; the nitroxide free radical TEMPO captures free radicals at low temperature and releases free radicals at high temperature, so that the molecular weight distribution is uniform, the initiator BPO and the solvent synergistically guarantee stable polymerization, the product is low in melt viscosity at 130-150 DEG C, small molecular chain segments are few, the molecular weight is large under the combined action of the three, and the hot-melt coating is realized while the cohesion strength is high.

The present application provides a surface treatment agent having excellent antithrombogenicity and biocompatibility, and high hydrophilicity compared with conventional medical materials. The present application is an antithrombogenic material comprising a (meth)acrylate copolymer containing a hydrophobic (meth)acrylate and a hydrophilic (meth)acrylate, the hydrophobic (meth)acrylate being a silicone (meth)acrylate and / or a (meth)acrylic acid alkyl ester, the (meth)acrylate copolymer having a residual monomer amount of 4,000 ppm or less, an inherent viscosity (ηsp / c) of 0.18 dl / g or more and 3.00 dl / g or less, the (meth)acrylate copolymer being water-insoluble, and being a viscous liquid at room temperature.

A reflective article comprising an injection molded thermoplastic substrate and a reflective metal layer disposed on a surface of the thermoplastic substrate. The injection molded thermoplastic substrate is prepared from a pre-blended composition comprising specific amounts of a hydrogenated block copolymer of two poly(phenylene ether)s having different inherent viscosities, a random polystyrene, and optionally an alkenyl aromatic compound and a conjugated diene. The reflective article is lighter and less costly compared to comparable reflective articles based on heat-resistant polycarbonates. Also described are a melt-blended composition derived from the pre-blended composition and an injection molded article prepared from the melt-blended composition.

The utility model belongs to the field of adhesive processing, particularly relates to a storage device for adhesive processing, and aims to solve the problems that the efficiency is reduced due to the fact that the discharging speed is low due to the viscosity of an adhesive, and residues can appear on the inner wall in the device. A feeding end is arranged on one side of the outer wall of the storage tank, a discharging end is arranged at the bottom of the storage tank, a discharging valve is arranged in the discharging end, an exhaust end is arranged on one side of the outer wall of the storage tank, and an air escape valve is arranged in the exhaust end. The discharging efficiency is improved, meanwhile, residual adhesive on the inner wall of the storage tank can be scraped out together, residues are reduced as much as possible, misoperation can be prevented, the phenomenon that the adhesive is directly added to the position above the piston plate is avoided, and therefore the practicability of the device is ensured.

The present invention relates to an amorphous copolyamide comprising the repeating units of general formula (I): X1F / X1Y1 (I) wherein X1F is a repeating unit obtained from the polycondensation of a diamine X1 with 4 to 18 carbon atoms and of F representing 2,5‐furandicarboxylic acid, X1Y1 is a repeating unit obtained from the polycondensation of the diamine X1 and of a diacid Y1 with 4 to 18 carbon atoms, provided that Y1 is not F. the copolyamide having an inherent viscosity of more than 0.85 dL / g, preferably more than 0.90 dL / g, and most preferably of more than 0.95 dL / g, the copolyamide having a glass transition temperature of between 115°C and 170°C.

A semi-aromatic polyamide resin comprising diamine units and dicarboxylic acid units, wherein the diamine units comprise 60-100 mol% aliphatic diamine units having 7-13 carbon atoms per 100 mol% of the diamine units, and the dicarboxylic acid units comprise 60-100 mol% aromatic dicarboxylic acid units per 100 mol% of the carboxylic acid units. The specific logarithmic viscosity η, measured in concentrated sulfuric acid at 30°C, is... inh The content of terminal amino group [NH2] is 1.6 to 3.0 dl / g, the content of terminal amino group [NH2] is 10 to 70 μequivalents / g, the content of terminal carboxyl group [COOH] is 10 to 90 μequivalents / g, and the ratio of the above-mentioned terminal amino group [NH2] to the above-mentioned terminal carboxyl group [COOH], i.e., [NH2] / [COOH] is 0.1 or more and less than 1.0.

The invention discloses polyimide molding powder, a preparation method of the polyimide molding powder, a polyimide molding profile and a preparation method of the polyimide molding profile, and relates to the field of high polymer materials, and the logarithmic viscosity of the polyimide molding powder is 70-150ml / g; and / or the particle size of the polyimide molding powder is 10-90 [mu] m. Compared with the prior art, the polyimide molding powder provided by the invention has proper logarithmic viscosity and particle size, has better processability and avoids the problems of undesirable phenomena and the like in the molding process when being applied to preparation of polyimide molding profiles; the high-temperature resistance, the mechanical property, the balance between a pressed surface and a non-pressed surface and the like of the obtained polyimide molded profile can be remarkably improved, so that the use requirements in different fields are met, and the application prospect is wide.

A copolyester composition of a diacid component and a glycol component is combined with a glass reinforcing material to provide a composition with enhanced optical properties and flowability properties. The diacid component includes residues of terephthalic acid. The glycol component includes cyclohexanedimethanol residues and 2, 2, 4, 4-tetramethylcyclobutane-1, 3-diol residues and the copolyester has an inherent viscosity of 0.7 dL / g or less. The glass reinforcing material is a glass fiber having a refractive index substantially equal to the refractive index of the copolyester composition.