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Baitong will continue to give full play to its comprehensive advantages in the field of wire mesh products, constantly meet customer needs, to provide high-quality products and services for global partners.
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Baitong will continue to give full play to its comprehensive advantages in the field of wire mesh products, constantly meet customer needs, to provide high-quality products and services for global partners.
What are the factors that affect the performance of wedge wire screen?
Release Time:
2022-12-20
Effect of wedge wire screen on isocyanate index. The isocyanate index refers to the molar ratio of polyisocyanate to oligomeric polyol. In the synthesis of prepolymer, the closer the NCO/OH ratio is to 1, the greater the viscosity of the prepolymer and the difficulty in pouring.
Effect of wedge wire screen on isocyanate index. The isocyanate index refers to the molar ratio of polyisocyanate to oligomeric polyol. In the synthesis of prepolymer, the closer the NCO/OH ratio is to 1, the greater the viscosity of the prepolymer and the difficulty in pouring. When the NCO/OH ratio exceeds 2, the viscosity of the prepolymer will decrease significantly, and it is easy to produce branching reaction or free isocyanate, the storage stability will decrease, and a large amount of isocyanate gas will volatilize during operation, which is harmful to health and pollutes Air. The ratio of NCO/OH is generally selected between 115 and 212, because within this ratio range, the viscosity of the prepolymer is moderate, the defoaming operation is easy, and the overall performance of the product is better.
Effect of wedge wire screen reaction temperature Increasing the mixing temperature of prepolymer and chain extender can improve the compression deformation performance, but the tensile strength and tear strength will decrease, and the life in the kettle and gel time will be shortened. too low mixing temperature
Effect of NCO content in wedge wire screens. The NCO content is an important index to characterize the quality of the prepolymer, and it is also an important basis for calculating the amount of chain extender.
The higher the content of the prepolymer, the lower the viscosity of the prepolymer, which is easy to defoam and mix, and the corresponding product hardness, strength and modulus are higher, but the life in the kettle is shortened, and the lower the content of the prepolymer, the product hardness, The strength and modulus are reduced, the viscosity is increased, and the life in the kettle is prolonged
The effect of wedge wire mesh molecular weight. The relative molecular mass of the oligomer polyol determines the density of the neutral group of the polyurethane elastomer. With the increase of the relative molecular mass of the oligomer polyol, the physical properties of the polyester polyurethane elastomer improve and the hydrolysis resistance decreases. With the increase of the relative molecular weight of oligomer polyols, the flexibility and hydrolysis resistance of ether polyurethane elastomers will increase, but the tensile strength and modulus will decrease.
Influence of Compounding Agents for Wedge Wire Screen In the production process, in order to increase the reaction speed, improve the processing performance and product performance, and reduce the cost, a small amount of accelerator is added if necessary to enhance its physical and mechanical properties.
On the one hand, solid chain extenders are not allowed. On the other hand, although it is beneficial to prolong the life of the kettle and improve the physical properties, it is not easy to degas and mix unevenly, so only a moderate temperature range can be used in actual operation.
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