Abstract:
The invention relates to an acrylic impact modifier having a core-shell structure that provides an acrylic impact modifier composition comprising (a) a rubber core containing an alkyl acrylate polymer comprising at least two layers having different cross-linking densities, and (b) a shell containing an alkyl methacrylate polymer; to a process for the preparation of the acrylic impact modifier; and to a poly(vinyl chloride) composition comprising it. The acrylic impact modifier imparting excellent impact resistance was invented by employing multi-stage polymerization and at the same time by controlling the swelling index of rubber particles by changing the degree of cross-linking from stage to stage. And the poly(vinyl chloride) comprising the impact modifier of the present invention has good weatherability as well as excellent impact strength.
Abstract:
The present invention relates to a preparation method of an acryl-based impact-reinforcement, and more particularly, to a preparation method of an acryl-based reinforcement prepared by blending latex having large particles and latex having small particles, being capable of enhancing impact-resistance of a polyvinyl chloride (PVC) resin. The present invention provides a method of preparing an acryl-based impact reinforcement comprising a step of blending a) 50 to 90 parts by weight of latex having large particles with a particle size of 200 to 500 nm and a core-shell structure and b) 10 to 50 parts by weight of latex having small particles with a paicle size of 60 to 140 nm and a core-shell structure. In addition, the present invention provides an impact-reinforcement prepared by the method of the present invention, and a polyvinyl chloride (PVC) composition comprising the same.
Abstract:
This invention relates a novel gene which is induced by water deficit and abscisic acid. The gene encodes for a transcription factor, particularly homeodomain-leucine zipper transcription factor which contains a transcriptional activation domain in the C-terminal region and a DNA-binding domain in the N-terminal region. The gene can be cloned into an expression vector to produce a recombinant DNA expression system suitable for insertion into cells to form a transgenic plant transformed with this gene. The gene of this invention can be also used to produce transgenic plants which exhibit enhanced resistance to drought.
Abstract:
A vertical pressure sensor having a fluid deforming pressure application unit, a sensor housing, a socket, a circuit board, a plurality of electrode terminals, and a plurality of electrical signal transmitting electrode rods. The pressure application unit includes a diaphragm to which strain gauges are attached. The socket surrounds a circumference of the diaphragm of the pressure application unit and includes a receiving passageway. The plurality of electrode terminals are provided at the upper end of the socket in a Wheatstone bridge circuit pattern. The plurality of electrode terminals protrude from the upper end of the socket to constitute an electrode tip. The circuit board connects to the plurality of electrode terminals to convert a pressure value into an electrical signal, and the plurality of electrode rods are connected to the circuit board to transmit the electrical signal outside.
Abstract:
Provided are an acrylic copolymer composition, a method for preparing an acrylic copolymer, and a vinyl chloride resin composition including the acrylic copolymer. The acrylic copolymer composition includes 5-15 wt % of a crosslinking agent and an alkyl acrylate monomer constituting an alkyl acrylate crosslinked polymer and 85-95 wt % of methyl methacrylate and at least one monomer selected from the group consisting of alkyl acrylate and alkyl methacrylate. Addition of the acrylic copolymer to the vinyl chloride resin composition enhances the foaming property of the vinyl chloride resin. Combination of the acrylic copolymer with an impact modifier further enhances the impact strength of the vinyl chloride resin.