Reinforcement and modification of Wuhan modern PVC
日期：2021/3/26 8:32:43 / 閱讀： / 來源：本站
Reinforcement and modification of Wuhan modern PVCHollow plate machine www.www.dressup9x.com
PVC can be reinforced and modified by nano particle composite, whisker composite and fiber composite (including glass fiber, vitamin, organic polymer fiber and its fabric, carbon fiber, boron fiber pile, etc.). The strength, rigidity, modulus, fatigue resistance, creep resistance, chemical corrosion resistance and heat resistance of PVC have been greatly improved after being reinforced and modified by glass fiber. It can be processed into water pipes, cables, corrugated plates, cooling towers and water tanks, and can also be made into granular materials to produce injection parts, which are widely used. Hollow plate machine www.www.dressup9x.com
The main preparation process of GF reinforced PVC composites can be divided into melting method, solution collapse method, fluidized bed method, papermaking and water suspension method. The strength characteristics of GF reinforced PVC largely depend on the bonding between GF and PVC. Gf with different surface treatment methods can achieve different modification effect, and the difference is large. Taking silane coupling agent as an example, the interfacial bonding strength between resin and fiber can be improved by silane coupling agent, which is affected by a series of complex factors, including nasal energy adsorption, polar adsorption, acid-base interaction, interpenetrating network and covalent bond reaction. Therefore, the sensitivity of components of interfacial River work to silane coupling agent must be considered. From the point of view of chemical structure, silicon burning coupling agent can be expressed by the general formula rsixx-o, where r refers to the organic group which can produce different degrees of affinity (including chemical reaction) with the resin matrix, and X refers to halogen or heavy group, which can make silicon atoms firmly bonded to the silate structure on the surface of GF through hydrolysis. Silane coupling agents with different active groups have different hydrolysis rate and binding force. Hollow plate machine www.www.dressup9x.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, which usually forms a continuous and uniform PU membrane with about 10 monolayers, and there are a lot of coupling agents in the gap between GF monofilaments. So,. It is generally considered that the appropriate amount of silane coupling agent is 0.1% ~ 0.2% of GF weight.
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. The GF reinforced PVC composite was prepared by using 5 ~ 10 mm chopped glass fiber. The GF length of the composite 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 composite were excellent. When the content of GF is 30%, the tensile strength and flexural strength of GF reinforced PVC composite are 110MPa, 190mpa, 2 times of RPVC, 8.8gpa and 8.9GPa, 3 times of RPVC, 140J / M and 4 times of RPVC, respectively; the coefficient of thermal expansion decreases to 2.23x10 - * C-1, and the thermal deformation temperature increases to 84c. Hollow plate machine www.www.dressup9x.com
There are many kinds of PVC foam products, mainly including hard foam materials and soft foam materials (such as sole materials, artificial leather, etc.). Microcellular plastics is a new foam material with a diameter of 1~ 10um and a density of 1X10* ~1x 10* /em2. Compared with non foaming plastics, the density of microcellular plastics can be reduced by 5% ~ 95%. After microcellular foaming, PVC can not only reduce density and save cost, but also have many excellent physical and mechanical properties, such as light weight, high impact strength, high toughness, good heat and sound insulation performance, electrical conductivity and so on. Rigid PVC low foaming profile is developed in the early 1970s, in which rigid PVC foaming profile is an ideal material with plastic instead of technology. It is easy to be processed by mechanical methods, similar to wood. It can be processed by all kinds of woodworking methods (such as nailing, drilling, planing, riveting and bonding), and can be welded. At present, people pay more and more attention to it.