Weekly topic: 8 wealth points for those who answer correctly, 2 wealth points for participation； Question 127
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What is the calendering effect? What are the ways to reduce its effects? Answer: During the calendering process, as the viscous plastic passes through the gap between the calender rolls, the linear macromolecules arrange themselves in an ordered manner along the calendering direction. Anisotropy of the product occurs? The physical and mechanical properties of the product differ in its longitudinal and transverse directions? This phenomenon is referred to as the rolling effect in rolling formation. Methods: Try to avoid using anisotropic lubricants, change the feeding direction, and improve the plasticity of the material; slow cooling after rolling can reduce the rolling effect.
Answer: Calendring effect: During the calendring process, thermoplastic plastics are subjected to high shear stress, causing the macromolecules to align in the direction of film progression. This results in anisotropy in the physical and mechanical properties of the formed film; this phenomenon is known as the calendring effect. Reason for occurrence: During the calendering process, thermoplastic plastics are subjected to high shear and tensile stresses; as a result, the polymer macromolecules align in the direction of calendering, leading to anisotropy in the physical and mechanical properties of the product – this is known as the calendering effect. Method to reduce it: Increasing the temperature of the material appropriately can improve its plasticity, enhance the movement of macromolecules, disrupt their ordered arrangement, and thus reduce the rolling effect ； Reducing the roller speed increases the calendering time and reduces the calendering effect ； With a low amount of material stored on the roller, the rolling effect is also reduced ； Increasing the thickness of the product can reduce the rolling effect ； Try to avoid using anisotropic coupling agents, and cool slowly after rolling; this facilitates the relaxation of aligned molecules and can also reduce the rolling effect.
Calendering effect: During the calendering process, thermoplastic plastics are subjected to high shear stress, causing the macromolecules to align in the direction of film progression. This results in anisotropy in the physical and mechanical properties of the formed film; this phenomenon is known as the calendering effect. Methods to reduce the effect: 1. Increasing the temperature of the material appropriately can enhance its plasticity, accelerate the movement of macromolecules, disrupt their ordered arrangement, and thereby reduce the rolling effect ； 2. Reducing the roller speed increases the calendering time and reduces the calendering effect ； 3. The amount of material stored on the roller is low, which also reduces the rolling effect ； 4. Increasing the thickness of the product can reduce the rolling effect ； 5. Try to avoid using anisotropic coupling agents; cooling slowly after rolling facilitates the relaxation of oriented molecules and can also reduce the rolling effect.
During the calendering process, the polymer is subjected to shear and tensile stresses; as a result, its molecules align in the direction of calendering, leading to anisotropy in the mechanical properties of the final product. Ways to reduce this effect include increasing the temperature of the rolled material to enhance its plasticity, as well as reducing the rolling speed
What is the calendering effect? What are the ways to reduce its effects? Answer: During the calendering process, due to the high shear forces acting on the thermoplastic, its macromolecules align in the direction of film progression, resulting in anisotropy in the physical and mechanical properties of the resulting film. This phenomenon is known as the calendering effect. Methods: Try to avoid using anisotropic lubricants, change the feeding direction, and improve the plasticity of the material; slow cooling after rolling can reduce the rolling effect.
Calendering effect: During the calendering process, thermoplastic plastics are subjected to high shear stress, causing the macromolecules to align in the direction of film formation. This results in anisotropy in the physical and mechanical properties of the resulting film; this phenomenon is known as the calendering effect. Methods to reduce this effect include increasing the temperature of the material, which enhances its plasticity, promotes movement of the macromolecules, and disrupts their orderly arrangement, thereby reducing the calendering effect； Reducing the roller speed increases the calendering time and reduces the calendering effect ； With a low amount of material stored on the roller, the rolling effect is also reduced ； Increasing the thickness of the product can reduce the rolling effect ； Try to avoid using anisotropic coupling agents, and cool slowly after rolling; this facilitates the relaxation of aligned molecules and can also reduce the rolling effect.
What is the calendering effect? What are the ways to reduce its effects? During the calendering process, as the viscous plastic passes through the gap between the calender rolls, the linear macromolecules align in a directional manner along the calendering direction. Anisotropy of the product occurs, with different physical and mechanical properties in the longitudinal and transverse directions of the product; this phenomenon is referred to as the rolling effect in rolling formation. Methods: Minimizing the use of anisotropic additives, changing the feeding direction, and improving the plasticity of the material, along with slow cooling after rolling, can reduce the rolling effect.
Calendering effect: During the calendering process, thermoplastic plastics are subjected to high shear stress, causing the macromolecules to align in the direction of film advancement. This results in anisotropy in the physical and mechanical properties of the formed film. Methods to reduce this effect include increasing the temperature of the material, which enhances its plasticity, promotes movement of the macromolecules, and disrupts their orderly arrangement, thereby reducing the calendering effect； Reducing the roller speed increases the calendering time and reduces the calendering effect ； With a low amount of material stored on the roller, the rolling effect is also reduced ； Increasing the thickness of the product can reduce the rolling effect ； Try to avoid using anisotropic coupling agents, and cooling slowly after rolling facilitates the relaxation of oriented molecules, which can also reduce the rolling effect
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This post was last edited by sdhzcxgqz on 2015-8-3 11:33. What is the calendering effect? What are the ways to reduce its effects? First, the molded material is melted and plasticized using various plasticizing devices; then, the plasticized melt is passed through the gaps between a series of rollers that rotate in opposite directions, where it undergoes compression and stretching to become a flat, continuous plastic mass. After cooling and shaping, along with appropriate post-treatment, plastic products in the form of films or sheets are obtained. During the calendering process, thermoplastic plastics are subjected to high shear stress; as a result, the macromolecules align in the direction of film advancement, causing the resulting film to exhibit anisotropic physical and mechanical properties. This phenomenon is known as the calendering effect
Answer: During the calendering process, as the viscous plastic passes through the gap between the calender rolls, the linear macromolecules arrange themselves in an ordered manner along the calendering direction. Anisotropy of the product occurs, with different physical and mechanical properties in the longitudinal and transverse directions of the product; this phenomenon is referred to as the rolling effect in rolling formation. ↑Temperature ； ↓Speed and speed ratio ； roll gap↑ ； Minimizing the use of anisotropic coupling agents, changing the feeding direction, and improving the plasticity of the material, along with slow cooling after rolling, can reduce the rolling effect.