Rigid PVC foam
DATE：2022/7/6 8:52:56 / READ： / SOURCE：This station
Rigid PVC foam
Rigid PVC foam is mainly used for insulation, heat preservation, sound insulation, shock proof, packaging and other materials, as well as floating and life-saving materials on water. Hollow board production line www.handern comThe difference between rigid PVC foams and flexible PVC foams is that solvents are used instead of plasticizers, and the solvents volatilize during molding to obtain rigid PVC foam products. Rigid PVC foams are mainly divided into high foaming and low foaming rigid polyoxyethylene foams. The general amount of foaming agent for high foaming products is 8-15 parts, and the general amount of foaming agent for low foaming products is 0.5-5 parts. Hollow board production line www.handern com
The molding of high foaming rigid PVC foam is low, (1) the formula of foaming rigid PVC foam prepared by the process is shown in table -3, in which the organic foaming agent is used in formula I and the inorganic foaming agent is used in formula II. High foaming rigid PVC foam formula raw material formula i/ mass part formula II / mass part PVC (suspension method) 100 PVC (lotion method) 50 tribasic lead sulfate 4~6 0.8~0.82 antimony trichloride (flame retardant) Trimethylphenol phosphate azodiisobutyronitrile 12~14 7~9
Azodicarbonamide sodium bicarbonate 1.2~1.3 12~13 ammonium bicarbonate 60~65 dichloromethane 50~60 dichloroethane 0.9~0.92
Urea barium stearate 2~3 butyl nitrite 11~12 6~7 triphenyl phosphate. Hollow board production line www.handern com
The production process of rigid PVC foam mainly adopts the pressing (Molding) molding process. In production, the solid components in the formula (foaming agent, stabilizer, flame retardant, etc.) are mixed and placed in a ball mill for grinding for 3~4h, and then screened (with a 60 mesh screen), and then the plasticizer Trimethylphenol phosphate and solvent are quickly added, stirred evenly, and loaded into the mold. The mold is heated and pressurized by a hydraulic machine for plasticization. The general pressure is 20MPa, and the heating steam pressure is 0.6MPa. The plasticization molding time depends on the size of the product. After complete plasticization, cool and demould, and put the product into boiling water or a drying room at 60~80 ℃ to continue foaming. Finally, the products can be shaped into foamed plastic products after heat treatment in the oven at (65 ± 5) ℃ for 48h· There are a lot of materials and equipment in the production process of rigid foamed plastics, so the workshop is well ventilated, and is equipped with fire-proof and explosion-proof devices to ensure safe production. Hollow board production line www.handern com
Low foaming rigid polyethylene sedimentation tank foam material micro foaming method. The molding of low foaming rigid polyvinyl chloride foam plastic universal reticulated good box self (1) the plasticizing formula of low foaming rigid polyvinyl chloride foam is shown in the table: the raw material name of low foaming rigid polyvinyl chloride foam plastic formula is polyvinyl chloride resin (k55-60) skinning method / limited parts of package / volume parts of impact modifier barium cadmium composite stabilizer 1001006-86~8 integrator (Phosphite) 2~3 epoxy esters 0,5~1 2~3 0.5-1 synthetic ester wax 1~2 foaming agent 1~1.5 1~2 1~1.5 3 dioctyl phthalate calcium carbonate 1~2 titanium dioxide citric acid 1~2 2~3 0.3 3~5 1~2 hi hollow board production line www.handern com
Forming method ① skinning method, also known as "celuka method", adopts special die, profiler and cooling device. The size of the die of the machine head is the same as the inner diameter of the shaper, and the core die is installed in the machine head, so the material expands inward during foaming. After extrusion, the material first contacts the wall of the shaper, and is cooled by the wall of the shaper before expansion, forming a layer of skin with a thickness of about 1mm and a smooth surface, so it is called skinning method. ② Free foaming method this method selects the die of the machine head which is smaller than the setting device and expands outward during foaming. This method is suitable for producing profiles with small cross-sectional area. The extruder adopts single screw type, and the head and die are modified to increase the back pressure, inhibit the foaming of materials in the extruder, and make them expand after leaving the die. The design of shaping and cooling device is the key to produce products with stable size and good skin. Hollow board production line www.handern com
Low foaming rigid PVC foamed plastic products are mainly produced in decorative parts, window frames, and shagguo Shenjin /8008~00
The skin is continuous and smooth, which is used to replace wood. Hollow board production line www.handern com
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