| Meltblown elastic nonwovens are made by melt blowing technology using thermoplastic elastomers which show good elastic recovery. They not only possess the property of normal meltbown nonwovens, but also have excellent elastic extensible and flexible performance which can be widely used in clothing, biological medical and filtration area. The application will go forward by the emergence of elastic polyolefin.The main chip used in melt blowing process is polyurethane now, meanwhile professor Larry C. Wadsworth from TANDEC made special research on it. Compared with meltblown polyurethane nonwoven, elastic polyolefin nonwovens show good chemical stability and light density moreover raw materials have low cost and the monomer can be easily manufactured using basic chemical materials. So the elastic polyolefin nonwovens can be partially in place of meltblown polyurethane, and the dissertation starts from this point.In contrast with overseas elastic polyolefin chips, domestic research on this material is just on the way. The materials were provided by Shanghai Gongcheng Polymers CO., Ltd which have two types of chips: before and after the modification. Through many experiment, the chips show good feasibililty of processability which can be directly made by melt blowing. The final nonwovens will be used as lining cloth and elastic layer in infant's diaper separately.The property of two chips named EPO1 (Elastic polyolefin) and EPO2 (Elastic polyolefin)were firstly experimental analysed. EPO polymer is pseudoplastic fluid and the non-Newtonian coefficient n increases with the rise of temperature, so it is a typical non-Newtonian fluid. Via differential thermal analysis, the melt temperature of EPO1 is 153.199°C;EPO2 chips show more complicatedly on DSC curve which have multi-melting points performance. We conclude that this chip is non-crystal blend by other analysis methods such as infrared and X-ray diffractive instruments. Via X-ray diffractive analysis, the result shows the degree of crystallization is higher than before.The whole process is carried out by Polymer System invented by Nonwoven research and development center of Donghua University. The meltblown process and its performance of web structure are investigated by altering parameters such as transversing layers, air temperature, air pressure and DCD. In the process of melt blowing, the blockage of spinneret was emerged due to high viscidity. In order to attenuate fiber successfully, air heater is reconstructed whose thickness has been changed from 3 mm to 6mm.Also it can be solved by changing air pressure and temperature.When the temperature-reduced mas-terbatch was added into melt chips EPO1, final testing demonstrates that breaking strength drop distinctly, from 4N to 2.5N. That reflects that temperature-reduced mas-terbatch plays a key role on elastic meltblown nonwovens.Elastic performance indicates the two type meltblown EPO nonwovens have higher elastic recovery, exceeds 30% and EPO2 nonwovens can reach to 88%.The breaking elongation of EPO1 can achieve around 110% and EPO2 arrives at about 400%. On the same condition of 0.6mm thickness, the heat insulation of meltbown EPO1 nonwovens is 37.21% which is slightly higher than the value of meltblown polyurethane nonwoven which has 36.27%. In the filtration, meltblown EPO1 has good performance and it can reach the obstructing and protecting action. Meanwhile amount of air permeation of EPO1 and EPO2 is very large and they can meet the needs of permeability of clothing lining and infant diaper.
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