JP2010202829A5

JP2010202829A5 -

Info

Publication number: JP2010202829A5
Application number: JP2009052195A
Authority: JP
Filing date: 2009-03-05
Publication date: 2012-03-15
Anticipated expiration: 2029-03-05

Description

[実施例１]
粘度平均分子量（Ｍｖ）２５万の高密度ポリエチレン「ＳＨ８００」（旭化成ケミカルズ（株）製、融点１３５．５℃）１２．８質量部、Ｍｖ１００万の超高分子量ポリエチレン「ＵＨ６５０」（旭化成ケミカルズ（株）製、融点１３６．６℃）１９．２質量部、平均一次粒径が１５ｎｍであるシリカ「ＬＰ」（（株）東ソー・シリカ製）２０質量部、酸化防止剤０．３質量部、可塑剤としてフタル酸ジヘキシル（ＤＯＰ）４８質量部をヘンシェルミキサーで混合して造粒した。その後、Ｔ−ダイを装着した二軸押出機にて２００℃で混練・押出し、厚さ１００μｍのシート状に成形した。該成形物から塩化メチレンにてＤＯＰを抽出除去し微多孔膜とした。該微多孔膜を２枚重ねて１３０℃に加熱のもとＭＤに５倍、ロールにて延伸した後、最大温度１４０℃に加熱のもとＴＤに１．７倍、テンターにて延伸した。
得られた膜は、ＭＤの引張強度２９ＭＰａ、ＴＤの引張強度５ＭＰａ、平均孔径０．２０μｍ、最大孔径０．２７μｍであった。製膜条件およびその他の膜特性を表１に示す。 [Example 1]
High-density polyethylene “SH800” with a viscosity average molecular weight (Mv) of 250,000 (manufactured by Asahi Kasei Chemicals Corporation, melting point 135.5 ° C.) 12.8 parts by mass, ultra high molecular weight polyethylene “UH650” with an Mv of 1,000,000 (Asahi Kasei Chemicals Corporation) ), Melting point 136.6 ° C.) 19.2 parts by mass, silica “LP” having an average primary particle size of 15 nm (manufactured by Tosoh Silica) 20 parts by mass, antioxidant 0.3 parts by mass, plastic As an agent, 48 parts by mass of dihexyl phthalate (DOP) was mixed with a Henschel mixer and granulated. Then, it knead | mixed and extruded at 200 degreeC with the twin-screw extruder equipped with T-die, and shape | molded in the sheet form of thickness 100 micrometers. DOP was extracted and removed from the molded product with methylene chloride to form a microporous membrane. Two of the microporous membranes were stacked and heated to 130 ° C. and stretched by MD and 5 times in a roll, and then heated to a maximum temperature of 140 ° C. and 1.7 times in TD and stretched by a tenter.
The obtained membrane had an MD tensile strength of 29 MPa, a TD tensile strength of 5 MPa, an average pore diameter of 0.20 μm, and a maximum pore diameter of 0.27 μm. Table 1 shows the film forming conditions and other film characteristics.