PVC reinforced and modified lining coating composite production line
DATE：2021/7/16 8:32:07 / READ： / SOURCE：This station
PVC reinforced and modified lining coating composite production line
PVC can be reinforced and modified by nano particle composite, whisker composite and fiber composite (including glass fiber, asbestos fiber, organic polymer fiber and its fabric, carbon fiber, boron fiber, etc.). The strength, stiffness, modulus, fatigue resistance, creep resistance, chemical corrosion resistance and heat resistance of PVC reinforced by glass fiber (GF) have been greatly improved. It can be processed into water pipes, cables, corrugated plates, cooling towers and water tanks, and can also be made into pellets to produce various injection parts, which are widely used. Lining coating composite production line www.handern.comThe main preparation processes of GF reinforced PVC composites can be divided into melting method, solution impregnation method, fluidized bed method, papermaking method and water suspension method. The strength properties of GF reinforced PVC depend on the interface between GF and PVC to a great extent. Gf with different surface treatment methods can achieve different modification effect, and the difference is large. Taking silane coupling agent as an example, improving the interfacial bonding strength between resin and fiber by silane coupling agent is affected by a series of complex factors, including interfacial energy adsorption, polar adsorption, acid-base interaction, interpenetrating network and covalent bond reaction. Therefore, the sensitivity of components on both sides of the interface to silane coupling agent must be considered. In terms of chemical structure, silane coupling agent can be expressed by the general formula R, six (~ n), where r refers to the organic group that can have different degrees of affinity (including chemical reaction) with the resin matrix, and X refers to halogen or alkoxy group, which can make silicon atoms firmly bonded to the silicate structure on the surface of GF through hydrolysis. Silane coupling agents with different active groups have different hydrolysis rate and binding force. Lining coating composite production line www.handern.com
The amount of coupling agent can be calculated properly and finally determined by the experimental results. However, it is impossible for the coupling agent to form an ideal monolayer on the surface of GF, but a continuous and uniform film with about 10 monolayers is usually formed, and there is a large amount of coupling agent in the gap between GF monofilaments. Therefore, it is generally considered that the appropriate amount of silane coupling agent is 0.1% ~ 0.2% of GF weight. Lining coating composite production line www.handern.com
The content of GF also has great influence on the mechanical properties of the composites. With the increase of GF content, some properties of the composites are improved. The properties of GF reinforced composites are also related to the actual length of GF. Therefore, the influence of processing conditions on GF must be paid attention to in the process of composite molding. The critical fiber length of GF / RPVC is 0.1 mm. GF reinforced PVC composites were prepared by using 5 ~ 10 mm chopped glass fiber. The GF length of the composites was between 0.18 ~ 0.64 mm by using appropriate process formula and processing conditions, which met the limit of critical fiber length. The properties of the composites were excellent. When the content of GF is 30%, the tensile strength and flexural strength of GF reinforced PVC composite are 110MPa and 190mpa, which are two times of RPVC. The tensile modulus is 8.8gpa and the content is 8.9GPa, which are three times of RPVC; The notched impact strength of cantilever beam is 140J / m, which is about 4 times of RPVC; The coefficient of thermal expansion decreases to 2.23x10 - ℃ - 1, and the hot deformation temperature increases to 84 ℃. Lining coating composite production line www.handern.com
Author：admin