摘要:
Semicrystalline sulphonic fluorinated ionomers having an equivalent weight higher than 700 g/eq, up to 1,700, comprising: (A) monomeric units deriving from one or more fluorinated monomers containing at least one ethylene unsaturation; (B) fluorinated monomeric units containing sulphonyl groups —SO2F in such amount to give the above equivalent weight, deriving from F2C═CF—O—(CF2)q—SO2F, q being an integer equal to 2 or 3; and having the following properties for a TFE/(B) copolymer: hydration, expressed in % of H2O at 100° C. absorbed by the film prepared from the ionomer and after tranformation from the —SO2F form into the —SO3H form, having the following values: at 750 EW higher than 55%, pref. >70% at 850 EW ″ 45%, ″ >55% at 1,000 EW ″ 35%, ″ >40% at 1,100 EW ″ 28%, ″ >32% at 1,200 EW ″ 23%, ″ >25%.
摘要:
A polymerization process in aqueous emulsion of: (I) one or more fluorinated monomers containing at least one ethylene unsaturation; (II) one or more fluorinated monomers, containing sulphonyl groups —SO2F; said process comprising the use of a surfactant having the formula: Rf—X−M+ wherein X is equal to —COO, —SO3; M is selected from H, NH4, alkaline metal; Rf represents a (per)fluoropolyether chain, preferably having number average molecular weight comprised between about 230 and about 1,800.
摘要翻译:水乳液中的聚合方法:(I)含有至少一个乙烯不饱和度的一种或多种氟化单体;(II)含有磺酰基-SO 2 F的一种或多种氟化单体;所述方法包括使用具有下式的表面活性剂: 其中X等于-COO,-SO 3; M选自H,NH 4,碱金属; R f表示(全)氟聚醚链,优选数均分子量在约230至约1800之间。
摘要:
A liquid composition comprising: at least one fluoroionomer (I) [fluoroionomer (I-1)], the fluoroionomer (I-1) having a heat of fusion comprised between 4 and 20 J/g; and at least one fluoroionomer (I) [fluoroionomer (I-2)], the fluoroionomer (I-2) being substantially amorphous, that is to say having a heat of fusion of less than 4 J/g, and wherein the water extractable fraction of the fluoroionomer (I-2) is less than 40% wt, the liquid composition comprising the fluoroionomer (I-1) and the fluoroionomer (I-2) in a weight ratio (I-1)/(I-2) of at least 2:1.
摘要:
A process for the purification from ionic impurities of a fluoroionomer liquid composition, comprising: providing a liquid composition comprising at least one fluoroionomer (I-1) in a liquid medium, the liquid composition comprising ionic impurities; contacting the liquid composition with a solid particulate comprising at least one fluoroionomer (I-2) having ion exchange groups, wherein H+ or OH− ions are bound to at least a fraction of such ion exchange groups, and separating the liquid composition from the solid particulate.
摘要:
A liquid composition comprising: at least one fluoroionomer (I) [fluoroionomer (I-1)], the fluoroionomer (I-1) having a heat of fusion comprised between 4 and 20 J/g; and at least one fluoroionomer (I) [fluoroionomer (I-2)], the fluoroionomer (I-2) being substantially amorphous, that is to say having a heat of fusion of less than 4 J/g, and wherein the water extractable fraction of the fluoroionomer (I-2) is less than 40% wt, the liquid composition comprising the fluoroionomer (I-1) and the fluoroionomer (I-2) in a weight ratio (I-1)/(I-2) of at least 2:1.
摘要:
A process for the purification from ionic impurities of a fluoroionomer liquid composition, comprising: providing a liquid composition comprising at least one fluoroionomer (I-1) in a liquid medium, the liquid composition comprising ionic impurities; contacting the liquid composition with a solid particulate comprising at least one fluoroionomer (I-2) having ion exchange groups, wherein H+ or OH− ions are bound to at least a fraction of such ion exchange groups, and separating the liquid composition from the solid particulate.
摘要:
The invention relates to a process for the isolation of (per)fluorinated polymers containing sulfonyl fluoride functional groups from a polymerization latex. The process comprises adding the polymerization latex to an aqueous electrolyte solution under high shear stirring at a temperature equal to or lower than the glass transition temperature of the polymer. The invention further relates to the (per)fluorinated polymers containing sulfonyl fluoride functional groups isolated by the process and characterised by a loss of weight at 200° C. lower than 1% as determined by thermogravimetric analysis.
摘要:
Microporous membrane composites that are non-dewetting are disclosed. These microporous membrane composites are wet with solutions of methanol and water and are non-dewetting following autoclave treatment in water. The microporous membrane composites comprise a microporous membrane support that is coated with a crosslinked ionomer comprising hydrophilic groups. Compared to the microporous membrane support, the microporous membrane composite has a flow loss on average in isopropyl alcohol of less than 82%.
摘要:
Microporous membrane composites that are non-dewetting are disclosed. These microporous membrane composites are wet with solutions of methanol and water and are non-dewetting following autoclave treatment in water. The microporous membrane composites comprise a microporous membrane support that is coated with a crosslinked ionomer comprising hydrophilic groups. Compared to the microporous membrane support, the microporous membrane composite has a flow loss on average in isopropyl alcohol of less than 82%.