| With the development of technology, a wide variety of adhesives for multifunction and high performance used widely in the modern industry has become an important kind of industrial and defensive material. Now the needs of environmentally friendly adhesives are increasing. As an environmentally friendly adhesive, much more polyvinyl acetate emulsion is produced. At present, its output is lower than urea-formaldehyde resin, which lives in the second. However, the use of polyvinyl acetate emulsion is limited due to its resistance properties including cold & water resistance, heat resistance, moisture resistance, mechanical stability and especially poor, long-term preservation of the shortcomings. In order to improve these properties and expand its application, a great deal of modification about PVAc latex, concerning chemical copolymerization and physical blending modification, has been researched. Among them. In this thesis, a new emulsion in accordance with the needs of industry has been obtained by the way of copolymerization and blending modification together. This paper discussed the following issues.1. The monomer ratio and variation of performance for the MMA & VAc have been studied as follows. (1) The polymerization of vinyl acetate emulsion solid content increased a lot with the MMA monomer added. However the storage stability of emulsion was decreased with the increasing of MMA monomer content. (2) With the increase of MMA content, the viscosity of emulsion copolymerization increased quickly, which was about 10 times than the origin, but when the MMA monomer content (percentage of total VAc monomer) was more than 15%, the emulsion viscosity change was not too great. And Emulsion solidification rate also declined.2. It has studied, when MMA and the VAc allocated proportion (12%) was certain, PF had an effect on the performance of the blending emulsion. (1) Along with PF contents increasing, the obtained blending emulsion's solid content change was not big, while the water resistance had further been improved. (2) Added the quantity along with the phenolics increasing, the emulsion freezing, thawing stability and the storage stability dropped. Simultaneously the emulsion shearing strength demonstrated the declining trend. When the PF content surpasses 2.5%, the emulsion shearing strength had a very obvious drop. (3) Phenolics monomer's join was not big to the influence of the blending emulsion's coagulation rate. But its starting stick force and the viscosity had the very big enhancement. At the same time, its cementation performance had had the very big improvement.3. This thesis has researched the blending emulsion properties on which MMA had an effect under the allocated certain 2% rate of PF and VAc. (1) Along with MMA content increasing, the solid content of the blending emulsion's improved very much. Meanwhile the water resistance, the original stick force, the freezing and thawing stability enhanced very quickly, which enabled the emulsion to adapt the many professional demands. (2) With the MMA content increasing, the shearing strength of the emulsion manifested the big trend of escalation. Simultaneously when the MMA content surpassed 12%, the emulsion shearing strength had the trend of escalation accompanying by the stabilized time of the emulsion dropping. (3) With the MMA content increasing, the coagulation rate of the emulsion increased quickly and the membrane performance was good.4. Through the above experiments the thesis drew the following conclusion. Enhancement for the water resistance, the freezing and thawing stability of the emulsion, which might lengthen the storage for the emulsion and basically meet with anticipated requirements, could been realized. The modified emulsion through the copolymerization blending modification is up to the properties of the GB/T 11175-2002. And also it is in accordance with the standard such as lumber, rubber.5. This thesis has demonstrated the preparation for the copolymerization blending rubber latex fluid and characterized the emulsion performance. (1)The results indicated that each emulsion stability, such as freezing and thawing stability, had the specially big enhancement compared to the PVAc emulsion, which could meet the anticipated requirements. (2) With the Yang trees testing, the modified emulsion's sticking strength was improved more than the PVAc with the coagulation rate reducing. Compared with the PVAc, the hardening time of the emulsion reduced, which achieved the lumber industrial standard. (3) The storage life of this modified latex fluid under the room temperature environment testing was about 11 months. When expired, the emulsion would possibly present the precipitation phenomenon. However the emulsion after the short-term expiring could been utilized again when shaking evenly.
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