Abstract: Disclosed are methods of determining the suitability of a variable-length spectrophotometer using Patent Blue dye or AMG Blue dye. Also disclosed herein are methods of determining the suitability of a fixed path length spectrophotometer for determining protein concentration of a protein sample. AMG Blue dye may also be used to determine the suitability of fixed path length spectrophotometers.

Abstract: Provided are methods for obtaining modified polyarylene sulfide compositions having improved thermal and thermo-oxidative stability, the compositions so obtained, and articles comprising the compositions. The method comprises the steps of contacting, in the presence of a suitable solvent, a polyarylene sulfide with at least one reducing agent and at least base to form a first mixture. The reducing agent comprises zinc(0), tin(0), tin(II), bismuth (0), bismuth(III), or a combination thereof. The first mixture is heated to form a second mixture in which the polyarylene sulfide is dissolved. The polyarylene sulfide is then precipitated to obtain a modified polyarylene sulfide.

Abstract: Provided are methods for obtaining modified polyarylene sulfide compositions having improved thermal and thermo-oxidative stability, the compositions so obtained, and articles comprising the compositions. The method comprises the steps of contacting, in the presence of a suitable solvent, a polyarylene sulfide with at least one reducing agent and at least base to form a first mixture. The reducing agent comprises zinc(0), tin(0), tin(II), bismuth (0), bismuth(III), or a combination thereof. The first mixture is heated to form a second mixture in which the polyarylene sulfide is dissolved. The polyarylene sulfide is then precipitated to obtain a modified polyarylene sulfide.

Abstract: Provided are methods for obtaining modified polyarylene sulfide compositions having improved thermal and thermo-oxidative stability, the compositions so obtained, and articles comprising the compositions. The method comprises the steps of contacting, in the presence of a suitable solvent, a polyarylene sulfide with at least one reducing agent and at least base to form a first mixture. The reducing agent comprises zinc(0), tin(0), tin(II), bismuth (0), bismuth(III), or a combination thereof. The first mixture is heated to form a second mixture in which the polyarylene sulfide is dissolved. The polyarylene sulfide is then precipitated to obtain a modified polyarylene sulfide.

Abstract: Provided are polyphenylene sulfide compositions having improved thermo-oxidative stability, methods for obtaining them, and articles comprising the compositions. The compositions comprise polyphenylene sulfide and a bismuth additive. The bismuth additive comprises a bismuth halide, an inorganic bismuth salt, a bismuth carboxylate, an oxide comprising bismuth and a transition metal, bismuth metal, or a mixture thereof. Optionally, the compositions further comprise at least one zinc(II) compound.

Abstract: An improved process for forming polyarylene sulfide fibers is provided. The process comprises forming at least one fiber from a polymer melt comprising a polyarylene sulfide and at least one tin additive comprising a branched tin(II) carboxylate. Using such a melt, the fiber forming continuity is improved compared to that of the native polyarylene sulfide melt processed under the same conditions.

Abstract: A method for accelerating the curing of a polyarylene sulfide. The polyarylene sulfide is blended with a cure accelerator to form a mixture where the weight percentage of accelerator is between 0.2% and 15.0% of the total weight of the blend. The mixture is cured at 320° C. or above for at least 20 minutes. The cure accelerator is a compound selected from the group consisting of ionomers, hindered phenols, polyhydric alcohols, polycarboxylates, and mixtures of the foregoing.

Abstract: A nonwoven web comprising bicomponent fibers. The fibers have continuous phases each of a first polyarylene sulfide (PAS) component and a polymer component. The polymer component may also be a second polyarylene sulfide. The first polyarylene sulfide component contains a tin or a zinc additive or both, and the first polyarylene sulfide component of any given fiber is at least partially exposed to the external surface of that fiber.

Abstract: A nonwoven web comprising bicomponent fibers. The fibers have continuous phases each of a first polyarylene sulfide (PAS) component and a polymer component. The polymer component may also be a second polyarylene sulfide. The first polyarylene sulfide component contains a tin or a zinc additive or both, and the first polyarylene sulfide component of any given fiber is at least partially exposed to the external surface of that fiber.

Abstract: A method for stabilizing a polymeric structure against thermo-oxidative degradation is described. A polymeric core structure is provided with a skin layer that contains a skin resin in which the skin resin at least partially envelops a portion of the core structure. The skin structure then provides a barrier that thereby stabilizes the portion of the structure that is enveloped. The skin resin is made from a treated polyarylene sulfide.

Abstract: A nonwoven felt for hot gas filtration. The fibers have a polyarylene sulfide (PAS) component that contains a zinc compound. In one embodiment, the PAS comprises at least one zinc(II) salt of an organic carboxylic acid. Also a method for filtering hot gases employing a bag made from a PAS component that contains a zinc or a zinc based additive.

Abstract: A polymer comprising polycyclic repeating units having recurring ion conducting groups and optional crosslinkable groups is disclosed. The present invention provides the capability of tailoring polymers to impart unique properties to membranes fabricated from the polymers. Membranes comprising the polymers and methods for preparing the membranes and their use in ion conducting membranes, particularly in fuel cells, are also provided.

Abstract: A polymer comprising polycyclic repeating units having recurring ion conducting groups and optional crosslinkable groups is disclosed. The present invention provides the capability of tailoring polymers to impart unique properties to membranes fabricated from the polymers. Membranes comprising the polymers and methods for preparing the membranes and their use in ion conducting membranes, particularly in fuel cells, are also provided.

Abstract: A polymer comprising polycyclic repeating units having recurring ion conducting groups and optional crosslinkable groups is disclosed. The present invention provides the capability of tailoring polymers to impart unique properties to membranes fabricated from the polymers. Membranes comprising the polymers and methods for preparing the membranes and their use in ion conducting membranes, particularly in fuel cells, are also provided.