摘要:
In a novel method of homo- or copolymerization of vinyl chloride, a specified coating agent is applied on the surfaces of the portions which will become into contact with the vinyl chloride monomer during the polymerization process. The coating agent is in a form of an aqueous solution of a modified condensation product of phenol and aldehyde, the pH of the solution being adjusted in a range that the product is dissolved at an ambient temperature upon coating of the solution and separates out of the solution upon being heated on the surfaces. The wall surface of the polymerization tank and the like is then coated with a thin film of the coating agent having a uniform thickness and being strongly adhered to the wall surface, thereby providing an excellent effect of preventing adhesion of the product polymer to the wall surface.
摘要:
A process for the continuous production of an ABS resin includes a step of polymerizing 100 parts by weight of a monomer component, which is composed of a styrene monomer and an acrylonitrile monomer or of their mixture and a vinyl monomer copolymerizable with at least one of the monomers, in the presence of 4 to 50 parts by weight of a rubbery polymer by continuous bulk and/or continuous solution polymerization to form a polymer of the monomer component as a continuous phase and particles of the rubbery polymer as a dispersed phase. The polymerization step comprises at least two substeps, one being a first-stage substep of forming particles of the rubbery polymer and the other a second-stage substep of adjusting the particle sizes of the particles. The first-stage substep is conducted in a polymerization system making use of a plug flow reactor or a batch polymerization reactor, and conducts polymerization at least until the particles are formed in the polymerization mixture. The second-stage substep increases the amount of the monomer component converted into the polymer compared with that in the particle forming substep, and reduces the particles size. A polycarbonate-ABS resin composition is also disclosed.
摘要:
A process for the (co)polymerization of a monomer material, which includes at least an acrylonitrile monomer as an essential component, is performed at a temperature of 80°C or higher by bulk or solution polymerization. The (co)polymerization is conducted in a reaction tank while allowing said monomer material to evaporate and form a vapor phase over the polymerization mixture. During the (co)polymerization, the temperature of the vapor phase is maintained in a range of from 30°C to 65°C and the polymerization is conducted without substantially releasing vapor, which is evaporated from the polymerization mixture, to an outside of the reaction tank. By cooling the valor phase of the reaction tank and maintaining its temperature in the 30°C to 65°C range, it is possible to avoid mixing of a gelled polymer in the product and also to effectively remove reaction heat at the time of the (co)polymerization.
摘要:
A laminate using a polymeric molded article as a substrate and having a light transparency, gas barrier properties and an excellent alkali resistance is obtainable by carrying out a surface treatment to deposit an oxide of at least one metal selected from the metal elements of groups 2, 8, 9, 10 and 11 of the periodic table, and then forming a gas barrier layer such as oxides of silicon, nitrides of silicon and carbides of silicon on the treated surface. The gas barrier layer is not peeled off from the polymeric molded article even after immersion in an alkali solution of pH 12 or more. The amount of the metal on the treated surface is preferably in the range of 5 x 10 14 atoms/cm 2 to 3 x 10 16 atoms/cm 2 in terms of the metal atoms per unit area. The practical performance of the laminate is not deteriorated during the patterning, by alkali etching, of a transparent conductive layer formed on the laminate.
摘要:
A transparent, rubber-modified styrene resin comprises 70 to 96 parts by weight of a copolymer formed of 20 to 70 wt.% of styrene monomer units and 30 to 80 wt.% of alkyl (meth)acrylate monomer units and 4 to 30 parts by weight of a rubbery polymer. The rubbery polymer is dispersed in the copolymer as particles having an average particle size of 0.1 to 2.0 µm. At least 70 wt.% of the rubbery polymer is a styrenebutadiene block copolymer which is formed of 5 to 50 wt.% of styrene units and 50 to 95 wt.% of butadiene units, has a viscosity in a range of 3 to 60 mPa.s when measured as a 5 wt.% styrene solution at 25°C and possesses a ratio (Mw/Mn) of a weight average molecular weight (Mw) to a number average molecular weight (Mn) in a range of 1.0 to 1.8. The copolymer and the rubbery polymer have substantially the same refractive index. Also disclosed is a production process of the transparent, rubber-modified styrene resin, which comprises polymerizing a styrene monomer and an alkyl (meth)acrylate to a high degree of polymerized conversion in the presence of the rubbery polymer so that the rubbery polymer is formed into particles while allowing the copolymer to occur with substantially the same refractive index as the rubbery polymer.
摘要:
An improved preparation process for an aromatic mononitro compound comprising reacting an aromatic compound with mixed acid consisting of nitric acid, sulfuric acid or phosphoric acid and water, wherein these flow to react with each other in a reactor comprising a tube inside of which more than one twisted tabular members are aligned in sequence in a manner that a front margin of a twisted tabular member is substantially perpendicular to an back margin of the preceding member, can resolve a number of problems such as an inadequate mixing efficiency, reduction of a reaction rate, associated voluminal increase/complication of a reactor and difficulty in securing safety as well as provide the aromatic mononitro compound with minimal amount of by-products in a considerably short period.
摘要:
A degradable copolymer obtained by heat-dehydration reaction of aromatic polycarbonate and aliphatic polyester in the presence of a catalyst, has degradability which cannot be exhibited by common aromatic polycarbonate, transparency equal to polycarbonate, thermal resistance which cannot be exhibited by common aliphatic polyester, melt flowability superior to common aromatic polycarbonate and other excellent characteristics, and thus can be widely used for processed articles which require severe properties.
摘要:
A thin microcrystalline silicon semiconductor film suitable for use as an intrinsic semiconductor layer in an amorphous silicon solar cell or the like comprises an amorphous phase with crystallites contained therein in the form of a prismatic or conical crystallite aggregate phase. Additional crystallites may be dispersed as individual crystallites in the amorphous phase. In the thin film, the crystalline fraction may preferably range from 5 to 80% and the crystallite size may preferably range from 2 to 1,000 nm. This thin film can be formed by first forming an initial film to a thickness in a range of from 2 nm to 100 nm at a deposition rate of from 0.01 nm/sec to 0.1 nm/sec on a substrate and then forming a principal film at a deposition rate of from 0.1 nm/sec to 2 nm/sec, for example, in accordance with RF plasma CVD.
摘要:
An olefin polymerization catalyst system comprises an organic transition metal compound and a support, the organic transition metal compound being soluble in an inert organic solvent and the support, which is insoluble in the solvent, comprises an organic high molecular compound which contains a specific carbonyl-having group. The catalyst system polymerizes an olefin in a high activity, provides polymer with high stereoregularity, prevents adhesion or fouling of either the polymer generated in the course of polymerization or an organic aluminum oxy compound on the inner wall of a reactor, leads to high bulk density of the polymer and significantly reduced levels of fisheye and/or gel generation on the processed item. High productivity, and high quality products are attainable when using the catalyst.