Coating production line of polypropylene grafted modified non woven waterproof cloth
DATE：2021/6/5 8:53:18 / READ： / SOURCE：This station
Coating production line of polypropylene grafted modified non woven waterproof cloth
In order to meet the application requirements, expand the scope of application, PP is often modified by blending and filling. However, PP is a non-polar polymer. Maleic anhydride grafted PP is developed to solve this problem. For example, the compatibility of PA Zero Connection Technology Co., Ltd., Sida modified General inorganic pit material and Guzhu home material with P, can prepare composite materials with excellent comprehensive performance, so the research of PP modification has been booming. The connection methods used are as follows. The solvent used for grafting PP solution in medium solution can be methyltea and xylene to benzene. After PP is completely dissolved at 100 ~ 140C, grafting monomer is added to initiate grafting reaction by means of free radical, oxidation or radiation. The advantages of solution method are low reaction temperature, mild reaction, low degradation degree of PP and high grafting rate. But the disadvantage is that the solvent is used in a large amount and difficult to recover. This method has been gradually eliminated in industrial production. Suspension grafting: suspension grafting of PP is a method of initiating reaction of PP powder, film or fiber with grafting monomer in aqueous phase without or with only a small amount of organic solvent. This method not only inherits the advantages of solution method, such as low reaction temperature, low degradation degree of PP, easy control of reaction, but also has no problem of solvent recovery, which is conducive to environmental protection. Melt grafting: this method is widely used at present. It is a grafting reaction in which monomer and initiator are added to PP in melt state. Generally, it is carried out on processing equipment such as single screw extruder and twin screw extruder. As the processing temperature is generally above 180 ℃, the boiling point of monomer is required to be high. MAH, acrylic acid (AA) and its esters can be used in this method. This method can graft PP directly onto the processing equipment without solvent, and can be used for mass production. However, dynamic composite has high stress path and serious PP swelling, which has a serious negative impact on material properties. Coating production line of non woven waterproof cloth www.handern.comOther monomers such as AA, methylenoic acid, lounei acid amine and DEM can be used to prepare PP by melting method. In recent years, more and more attention has been paid to the role of the third body in correcting PP. Third, the addition of monomer can improve the grafting rate and inhibit the drop of vision of PP. For example, the mechanism of GMA / S (styrene) double monomer melt grafting PP was analyzed in detail. It was considered that the addition of comonomer S. could effectively inhibit the degradation of PP while increasing the grafting rate, because PP was removed under the action of free radicals. Because the anti seat activity of ST is higher than that of GMA, s will go up to PP first to form a relatively stable s: radical macromolecular free radical, so the new tendency of PP chain will be greatly stretched, and the reaction rate between ST radical macromolecular free radical and GMA is much higher than that between GMA and PP macromolecular free radical, Therefore, the grafting rate can be increased. The study of MAH / St double monomer melt grafting of PP has also drawn similar conclusions. The presence of the second monomer (st) can not only improve the grafting rate of MAH, but also reduce the degradation of PP. the solid phase grafting technology is a better method which can be widely used in the grafting technology modification of various compounds. The method is generally to mix PP solid with appropriate amount of monomers under the protection of n, The graft polymerization was initiated by initiator at 100 ~ 120 ℃. Solid PP can be film, fiber and powder, but the solid grafting is mainly for powder PP. Coating production line of non woven waterproof cloth www.handern.com
Compared with other grafting methods, solid-phase grafting has many obvious advantages: the reaction is carried out at a lower temperature (100 ~ 120 ℃), the powder PP hardly degrades, the solvent is not used or only a small amount of solvent is used as surfactant, and the solvent is absorbed by the surface of PP without national income; At the end of the reaction, the unreacted initiator and monomer can be removed by heating up and passing n; The reaction time is short, the grafting rate is high and the equipment is simple. Using BPO as initiator, MAH was grafted onto powdered PP by solid-phase grafting method. At the same time, PP-g-GMA graft was synthesized by solid-phase grafting method. The graft ratio of the product was 4% ~ 6%, and suitable amount of non-woven waterproof cloth coating production line was established www.handern.com
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