Production line of compatibilizing PVB auto glass laminated film by plastic blending
DATE：2021/6/10 8:40:13 / READ： / SOURCE：This station
Production line of compatibilizing PVB auto glass laminated film by plastic blending
In fact, most polymer polymer blends are thermodynamically incompatible or semi compatible. In other words, generally speaking, the compatibility of polymer polymer blends is not good. In order to obtain good physical and mechanical properties, it is necessary to improve the polymer polymer compatibility. Capacity increase is a common method. PVB auto glass laminated film production linewww.handern.com
Types of Compatibilization: from the perspective of Compatibilization mechanism, compatibilization can be divided into non reactive compatibilization and reactive compatibilization. Block copolymers and graft copolymers are commonly used as compatibilizers in non reactive compatibilization. One component is compatible with one component in the blend, and the other component is compatible with another component in the blend. According to the difference of microphase separation behavior of compatibilizers, the compatibilizers used can be divided into microphase separation type and homogeneous type. The former is represented by block copolymer and graft copolymer, while the latter includes random copolymer, functionalized polymer and homopolymer. Reactive compatibilization refers to compatibilization with reactive compatibilizer and direct reaction between components. PVB auto glass laminated film production line www.handern.com
The physical essence of Compatibilization can be summarized in three aspects; The interfacial tension between the blending components was reduced and the dispersion was improved; The stability of phase structure was improved, so that the properties of blending modified plastics were stable; Improving the interfacial adhesion between the components is conducive to the transfer of external field effect between the components, and improves the properties of the blend modified plastics. In order to make the compatibilizer play a full role, it is expected that the compatibilizer will gather in the interface region. In fact, the distribution of compatibilizer in blends is related to many factors. In addition to the compatibility, it is also related to the amount and method of compatibilizer, blending equipment and process conditions. PVB auto glass laminated film production line www.handern.com
The type of compatibilizer (1) block copolymers in theory, block copolymers can be arbitrarily combined into a variety of copolymers, copolymerization using monomers with different structures, in which one monomer can react with one polymer, the other monomer has good compatibility or reactivity with other components. When the concentration of the block copolymer reaches a certain value, the interface of the blend is saturated by the block copolymer. When the concentration of the block copolymer continues to increase, the excess block copolymer will form micelles in a homopolymer phase region, which is called critical micelle concentration (CMC). When the concentration of compatibilizer reaches DCMC, the interfacial tension will not continue to decrease with the increase of the content of compatibilizer. When the total molecular weight of the diblock copolymer remains unchanged, the volume fraction of the diblock components will affect the compatibilization of the blends. The special interaction between compatibilizer and blend components, such as hydrogen bond, will improve the compatibilization effect. For example, when PSB PVP (polystyrene grafted polyvinylpyrrolidone) compatibilizes PS / pvph, PS / pvba (polystyrene / poly (p-vinylbenzoic acid) and PS / PVP (polystyrene / poly (p-vinylpyrrolidone), the interfacial residual of ps-bpvp in PS / pvph and PS / pvba blends is significantly higher than that in PS / PVP blends. In the first two blends, the interface is almost completely occupied by the block copolymer, and the molecular chain is fully extended. The reason lies in the strong hydrogen bond between PvP and pvph, pvba. The compatibilization of triblock copolymer is stronger than that of diblock copolymer under the same composition and total molecular weight of block copolymer. PVB auto glass laminated film production line www.handern.com
(2) Graft copolymer is more convenient as compatibilizer because it is easy to synthesize. When one end of the molecular chain (preferably the main chain) is distributed on the phase interface, the compatibilization effect is better. For example, in PC / pcgpmma / PMMA blends, the more the number of branched chains connected to the PC chain, the worse the compatibilization effect of the graft copolymer. This is mainly due to the different steric hindrance of the grafted copolymers due to the different number of branched chains. There is a special kind of graft copolymers, whose main chain contains not only branched chains but also reactive functional groups. A typical example is the graft copolymer of maleic anhydride (MAH) (pp-mah) - gpeo (polyoxyethylene). When the grafted copolymer is used as compatibilizer, there are three kinds of Compatibilization: first, if the polar component of the blend does not contain groups which can react with MAH easily, but has good compatibility with PEO branched chain, the PEO branched chain is the main compatibilizer of the polar component; Secondly, if the polar component of the blend contains groups which are easy to react with MAH, but the compatibility with PEO branched chain is not good, MAH functional group is the main compatibilizer; Thirdly, if the polar component in the blend has both groups which are easy to react with MAH and are compatible with PEO branched chain, MAH functional group and PEO branched chain will play a compatibilizing role. The graft copolymer has good compatibilization effect on PP / TPU. PVB auto glass laminated film production line www.handern.com
(3) Reactive compatibilizer reactive compatibilization is produced in situ in the process of polymer mixing. At least two of the blending components are polymers with reactive groups. The reactive compatibilization system should have the following characteristics: the blend should have enough dispersion; The reaction rate between the functional groups of the two components should be large enough. PVB auto glass laminated film production line www.handern.com
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