Fundamental Study On Soluble Packaging Film Of Lubricant Viscosity Index Improver

The soluble packaging film used in the production of lubricating oil viscosity index improver is expensive and long-term depends on the import,which greatly improves the production cost of the product.Therefore,it is urgent to select the appropriate polyolefin copolymer material to develop the soluble packaging film.In this paper,the research on the crystallization properties of polyolefin copolymers and the application properties of thin films was carried out in view of this key technical problem.In order to determine the main raw material of the soluble packaging film,this paper has carried on the structural analysis and the application performance test to the two kinds of packaging film(sample film A and sample film B)which the enterprise is using.The results show that the sample film A is a polypropylene type copolymerized polyolefin elastomer material and contains a small amount of the separating agent.The sample film B is a polyethylene type copolymerized polyolefin elastomer material The The dissolution performance and mechanical properties of the two samples were tested by UV spectrophotometer and universal material testing machine.It was found that the mechanical properties of the sample film A were better,but the dissolution performance of the sample film B was better.The soluble packaging film has a higher requirement for the solubility of the material,and finally the main component of the sample film B(polyethylene type polyolefin elastomer)is selected as a raw material.In the process of solubility test,a method for characterizing the solubility of soluble film in base oil and the storage stability of low temperature was designed based on the solution transmittance.A kind of block copolymerized olefin(OBC 86-1)and five kinds of ethylene-octene random copolymers(EO 87-5,EO 87-1,EO 875-3,EO 875-1,EO 885-1)were selected according to the analysis results of existing soluble films,which were prepared as thin films by melt-cold pressing at 130℃,150℃,170℃ and 190℃ respectively.Firstly,the crystallization properties of different films were analyzed.The results of XRD,DSC and PLM show that the crystallinity of the prepared films is higher when the melting temperature is 150℃.Among them,the crystallinity of OBC film is much smaller than that of EO film,but only OBC material can form a more complete spherulite structure,and EO material mainly forms the shape and fiber structure.It was found that with the increase of crystallinity,the open-film performance and mechanical properties of the film samples were improved and the dissolution performance decrease;the dissolution performance of OBC 86-1 and EO 87-1 in the base oil is higher than that of the sample membranes and the EO 885-1 film has the best open-film performance.Based on this result,two techniques and options for the preparation of soluble film were proposed,which is:(1)OBC 86-1 and EO 885-1 were processed by multilayer film coextrusion technique;(2)EO 87-1 and EO 875-1 with a certain percentage of blending to film processing.