Improvement method for plastic PPR crazing whitening defects

Abstract

The invention discloses an improvement method of plastic PPR crazing whitening defects, which comprises the following steps of: firstly, detecting all crazing cavities of a polymer body; then fillingthe crazing cavities with five-micron particles; and fusing the crazing cavities with the polymer body by using a nucleating agent, internal and external lubricants and specially-made polymer particles to form a complex. The density of the crazing cavities is 50% of that of the polymer body, the refractive index is lower than that of the polymer body, and the interface between the crazing and thepolymer body generates a total reflection phenomenon on light rays, so that the crazing cavities present silver flashing lines. Through particle filling, light transmission is not prone to occurring,the whitening phenomenon is eliminated, the dense crazing cavities are fused with the surrounding polymer, expansion of crazing cavity cracks is retarded, toughness is improved, a pinning effect is generated, a firm structure is formed, and the impact resistance is enhanced. The crazing cavities are filled with the special polymer particles, the compactness of the crazing cavities, which is only 50% of the body density, is improved, the total reflection phenomenon is reduced, and therefore the silver light phenomenon is eliminated.

Description

technical field [0001] The invention belongs to the field of improving whitening of silver streaks, in particular to an improvement method for whitening defects of plastic PPR silver streaks. Background technique [0002] The defect of the silver streak phenomenon is mainly caused by various factors in the processing process; and in the prior art, thermoplastics or thermosetting plastics are processed into plastic products of various shapes through machinery and equipment and plastic molding molds, which are easy to appear. The whitening phenomenon of silver streaks; its main defect is: silver streaks appear between plastic PPR polymers to produce cross-sectional gaps and whitening, cracks are easy to expand under external force, and low-temperature impact resistance decreases. [0003] Due to the strain softening and tensile stress of the plastic polymer, the polymer macromolecules and micro-aggregates in the local plastic deformation zone continue to deform, and compound e...

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