Research On Polyolefin Fiber And Structure And Property Of Battery Separator Paper

With the rapid development of the times and technology, the application of the battery is in a gradual increase in people’s lives. Therefore, the development and production of high-quality battery is getting attentions, and the performance is one of the important factors. It becomes more important for development and production of the high quality battery separator paper. The paper is mainly studied on the structure and properties of polyolefin fibers and battery separator paper.We can use the polyolefin fiber as main material. It is based on using traditional papermaking method combined with wet nonwoven production technology to produce high uniformity, high-quality battery separator paper.Through the research analysis to the ES fiber, we can conclude that the average length is 5.415mm, average breadth is 16.11um of ES fiber. Under the observation of SEM, We can find some oil impurities on the fiber surface. We need to pretreat fiber before using. At the circumstance of room temperature 25℃,65% relative humidity. The ES fiber whose water absorption is low and hydrophilic is poor is just about 0.028%. ES fiber has the better corrosion-resistant performance on acid/alkali than other fibers. The weight-loss-rate hardly exceed 3% under the condition of alkali. It is easy to be corroded with the surface roughening but the weight loss rate is no more than 10%. Compared to other plant fibers and inorganic fibers, ES fibers still have the stronger ability of antiacid/antialkali.Because the hydrophilic of polyolefin fibers is poor, the length of fiber is long and difficult to dispersion resulting in poor paper evenness, this article take a study on how to improve the ES fibers dispersion properties in water in order to improve the papers evenness, strength and etc.The basic condition of fiber dispersion is based on experimental result:ES fiber use the Sodium dodecyl benzene sulfonate as pretreatment, with the concentration of 0.04% suspension after drying,then defibering for 2 minutes. Both water-soluble polymer and inorganic electrolytes can ameliorate fibers dispersion performance, but the effect of Hexametaphosphate is less than APMP、PEO、CMC. we finally take 0.3% PEO into pulp suspension, the addition of surfactant disperse single ES fiber better and fatty alcohol ether sulfate is better than sodium dodecyl sulfate. When use 4% AES, whichever the whole fiber or the single fiber get better dispersion. We use the 98%(Quality Score) concentrated sulfuric acid process the ES fiber, the fiber’s hydrophilic properties is increased and dispersion properties on water is improved because of great quantity of grafted-SO4H. Experiments show that overall fiber’s dispersion is better after 15 minutes sulfonation.To raise the strength and Alkali absorption of battery separator paper,we draw a conclusion that the optimal hot pressing temperature is 135℃ because more contact of the fusion bonding between the fibers,which make paper strength get a certain extent improvement and favourable distribution of fiber bore diameter and it has preferable influence on Alkaline absorbing height and Alkaline absorbing rate.lt has a certain extent inhibitory action to air bubble in soliquoid with 0.03% using level of deformer agent.With 10% PAC solution mixed in,the fibre soliquoid get a good effect on reinforcing punctate or mass combination, which improve the strength of battery separator paper to 37.4 Nm/g. Even the Alkali dissolution rate get a certain degree of reducing, it has small influence on Application Performance of Battery separator paper. When mix 10% replace amount PVA fiber,5.530mm average length and 15.8 μn average width, in the performance indicators of paper is relatively high, the tensile strength gets 45.2 Nm/g,3.62% alkali dissolution rate and 57.1mm/10min suction base height. Take concentrated sulfuric acid as sulfonation agent to battery separator paper and the processed papers hydrophilicity is improved via gradually introduced hydrophilic groups on paper surface. After processed by 98% concentrated sulfuric acid for 10 min, the paper can reach 52.2 Nm/g tensile strength,595% suction base rate and 57.8mm/10min suction base height.