The instant disclosure relates to a method for manufacturing a transparent polyimide film, including providing a polyamic acid solution having a fluorine content more than 12%; adding a dehydrating agent and a catalyst into the polyamic acid solution, the dehydrating agent having an equivalent number equal to or larger than 3; and baking the polyamic acid solution under a temperature ranging from 250 to 350 C. for performing a chemical imidization process so that the transparent polyimide film is obtained. The transparent polyimide film has an elongation rate of more than 30% and a b* value in a CIELAB coordinate of less than 3.5.

A membrane for a closed system transfer device including a material having 40-50% styrenic block copolymer, 0-10% polypropylene, and 45-60% by weight of mineral oil. The membrane may be utilized in any component of a closed system transfer device or system, such as a syringe adapter, patient connector, vial adapter, IV bag spike, etc. The membrane may also be utilized in scenarios where the cannula of the syringe adapter punctures the membrane and remains in the punctured position for an extended period of time, such as one hour or greater.

Described herein are anionic phenylene oligomers and polymers, and devices including these materials. The oligomers and polymers can be prepared in a convenient and well-controlled manner, and can be used in cation exchange membranes. Also described is the controlled synthesis of anionic phenylene monomers and their use in synthesizing anionic oligomers and polymers, with precise control of the position and number of anionic groups.

A cation exchange resin having improved chemical properties and mechanical properties, and a cation exchange membrane and an electrolyte membrane for a fuel cell using the same are provided.

A cation exchange resin is used, the cation exchange resin comprising: a divalent hydrophobic unit; and a divalent hydrophilic unit having divalent hydrophilic groups which are repeated via carbon-carbon bond, the divalent hydrophilic groups being composed of one aromatic ring, or being composed of a plurality of aromatic rings which are bonded to each other via a divalent hydrocarbon group, a divalent silicon-containing group, a divalent nitrogen-containing group, a divalent phosphorus-containing group, a divalent oxygen-containing group, a divalent sulfur-containing group, or carbon-carbon bond, at least one of the aromatic rings having a cation exchange group; wherein the hydrophobic unit and the hydrophilic unit are bonded to each other via carbon-carbon bond.

The present invention introduces ionic polymers featuring with a spiro structure, which enhances the solubility and gas permeability of the ionic polymer while maintaining excellent conductivity, mechanical properties, and dimensional stability. This is achieved by incorporating a spiro fragment with a large free volume into the polymer backbone. As a result, the gas permeability of the catalyst layer prepared from this ionic polymer is improved, making it suitable as a catalyst binder for proton exchange membrane fuel cells (PEMFCs) or anion exchange membrane fuel cells (AEMFCs). Furthermore, the electrochemical performance of the fuel cell is enhanced. Additionally, the proton exchange membrane and anion exchange membrane derived from this ionic polymer containing a spiro structure effectively improve the conductivity of both types of membranes by increasing the space volume due to the presence of the large free volume spiro fragment.

The present disclosure relates to polymers synthesized from ionomers having an aromatic hydrocarbon-containing backbone and an amine-containing ionic or ionizable moiety with polystyrene. The linkage between the ionomer and the polystyrene is made through covalent bonds or linking moieties. Electrochemical cells having polymer electrolyte membranes composed of the combined polymers are also described.

An ion exchange membrane is provided. The ion exchange membrane includes a reaction product of a polymer and a cross-linking reagent. The polymer includes a first repeat unit, and a second repeat unit. In particular, the first repeat unit is ##STR00001##
and, the second repeat unit is ##STR00002##
wherein R.sup.+ is ##STR00003##
A.sup. is F.sup., Cl.sup., Br.sup., I.sup., OH.sup., HCO.sub.3.sup., HSO.sub.4.sup., SbF.sub.6.sup., BF.sub.4.sup., H.sub.2PO.sub.4.sup., H.sub.2PO.sub.3.sup., or H.sub.2PO.sub.2.sup.; X is CH.sub.2.sub.iYCH.sub.2.sub.j, i and j are independently 0, or an integer from 1 to 4; Y is O, S, CH.sub.2, or NH; R.sup.1 is independently C.sub.1-8 alkyl group; and, R.sup.2 and R.sup.3 are hydrogen, or independently C.sub.1-8 alkyl group; and, the cross-linking reagent is a compound having at least two imide groups.

An ion exchange membrane is provided. The ion exchange membrane includes a reaction product of a polymer and a cross-linking reagent. The polymer includes a first repeat unit, and a second repeat unit. In particular, the first repeat unit is

##STR00001##

and, the second repeat unit is

##STR00002##

wherein R.sup.+ is

##STR00003##

A.sup. is F.sup., Cl.sup., Br.sup., I.sup., OH.sup., HCO.sub.3.sup., HSO.sub.4.sup., SbF.sub.6.sup., BF.sub.4.sup., H.sub.2PO.sub.4.sup., H.sub.2PO.sub.3.sup., or H.sub.2PO.sub.2.sup.; X is CH.sub.2.sub.iYCH.sub.2.sub.j, i and j are independently 0, or an integer from 1 to 4; Y is O, S, CH.sub.2, or NH; R.sup.1 is independently C.sub.1-8 alkyl group; and, R.sup.2 and R.sup.3 are hydrogen, or independently C.sub.1-8 alkyl group; and, the cross-linking reagent is a compound having at least two imide groups.

This patent is provided a method for producing a porous polymer film using vanadium oxide nanowires, and a porous polymer film obtained from the method. The method allows control of a uniform pore size and density through a simple process including the steps of: adding an ion exchanger to deionized water to perform acidification and adding a vanadate compound thereto to grow vanadium oxide nanowires by a sol-gel process; mixing the resultant solution of grown nanowires with a polymer solution to provide a mixed solution of nanowires; pouring the mixed solution of nanowires to a mold, followed by drying and curing, to form a film; and etching the resultant film with an etching solution to remove the vanadium oxide nanowires.

Provided herein are membrane electrode assemblies (MEAs) for CO.sub.x reduction. According to various embodiments, the MEAs are configured to address challenges particular to CO.sub.x including managing water in the MEA. Bipolar and anion-exchange membrane (AEM)-only MEAs are described along with components thereof and related methods of fabrication.