Abstract: Processes for forming a yarn comprising a plurality of bicomponent filaments having a first region comprising a first polymer composition and a second region comprising a second polymer composition; the regions being distinct and present in the bicomponent filaments in a sheath-core structure or a side-by-side structure; wherein the first polymer composition comprises aramid polymer comprising 5 to 10 weight percent homogeneously dispersed discrete carbon particles and the second polymer composition comprises aramid polymer being free of discrete carbon particles and having at least one homogeneously dispersed masking pigment, the yarn having a total content of 0.5 to 5 weight percent discrete carbon particles.

Abstract: A flame-resistant garment comprising a flame-resistant fabric, and the flame resistant fabric, each comprising a yarn comprising a) 85 to 97 weight percent of a meta-aramid fiber component, and b) 3 to 15 weight percent of a fiber made from para-aramid polymer, based on the total amount of a) and b) in the yarn; wherein the meta-aramid fiber component is: i) 50 to 100 weight percent fiber made from a polymer blend of meta-aramid polymer and polyvinylpyrrolidone (PVP) polymer, the polymer blend comprising 88 to 95 weight percent meta-aramid polymer and 5 to 12 weight percent PVP polymer, and ii) 0 to 50 weight percent fiber made solely from meta-aramid polymer, based on the total amount of i) and ii) in the meta-aramid fiber component.

Abstract: A yarn comprising a plurality of bicomponent filaments having a first region comprising a first polymer composition and a second region comprising a second polymer composition, each of the first and second regions being distinct in the bicomponent filaments; each bicomponent filament comprising 5 to 60 weight percent of the first polymer composition and 95 to 40 weight percent of the second polymer composition; wherein the first polymer composition comprises aramid polymer containing 0.5 to 20 weight percent discrete homogeneously dispersed carbon particles and the second polymer composition comprises modacrylic polymer being free of discrete carbon particles; the yarn having a total content of 0.1 to 5 weight percent discrete carbon particles.

Abstract: Processes for forming a yarn comprising a plurality of bicomponent filaments having a first region comprising a first polymer composition and a second region comprising a second polymer composition; the regions being distinct and present in the bicomponent filaments in a sheath-core structure or a side-by-side structure; wherein the first polymer composition comprises aramid polymer comprising 5 to 10 weight percent homogeneously dispersed discrete carbon particles and the second polymer composition comprises aramid polymer being free of discrete carbon particles and having at least one homogeneously dispersed masking pigment, the yarn having a total content of 0.5 to 5 weight percent discrete carbon particles.

Abstract: A yarn comprising a plurality of bicomponent filaments having a first region comprising a first polymer composition and a second region comprising a second polymer composition; the regions being distinct and present in the bicomponent filaments in a sheath-core structure or a side-by-side structure; wherein the first polymer composition comprises aramid polymer containing 0.5 to 20 weight percent homogeneously dispersed discrete carbon particles and the second polymer composition comprises aramid polymer being free of discrete carbon particles and having at least one homogeneously dispersed masking pigment, the yarn having a total content of 0.5 to 5 weight percent discrete carbon particles.

Abstract: A yarn comprising a plurality of bicomponent filaments having a first region comprising a first polymer composition and a second region comprising a second polymer composition, each of the first and second regions being distinct in the bicomponent filaments; each bicomponent filament comprising 5 to 60 weight percent of the first polymer composition and 95 to 40 weight percent of the second polymer composition; wherein the first polymer composition comprises aramid polymer containing 0.5 to 20 weight percent discrete homogeneously dispersed carbon particles and the second polymer composition comprises modacrylic polymer being free of discrete carbon particles; the yarn having a total content of 0.1 to 5 weight percent discrete carbon particles.

Abstract: A yarn comprising a plurality of bicomponent filaments having a first region comprising a first polymer composition and a second region comprising a second polymer composition, each of the first and second regions being distinct in the bicomponent filaments; each bicomponent filament comprising 5 to 60 weight percent of the first polymer composition and 95 to 40 weight percent of the second polymer composition; wherein the first polymer composition comprises aramid polymer containing 0.5 to 20 weight percent discrete homogeneously dispersed carbon particles and the second polymer composition comprises modacrylic polymer being free of discrete carbon particles; the yarn having a total content of 0.1 to 5 weight percent discrete carbon particles.

Abstract: A yarn comprising a plurality of bicomponent filaments having a first region comprising a first polymer composition and a second region comprising a second polymer composition, each of the first and second regions being distinct in the bicomponent filaments; each bicomponent filament comprising 5 to 60 weight percent of the first polymer composition and 95 to 40 weight percent of the second polymer composition; wherein the first polymer composition comprises aramid polymer containing 0.5 to 20 weight percent discrete homogeneously dispersed carbon particles and the second polymer composition comprises modacrylic polymer being free of discrete carbon particles; the yarn having a total content of 0.1 to 5 weight percent discrete carbon particles.

Abstract: A yarn comprising a plurality of bicomponent filaments having a first region comprising a first polymer composition and a second region comprising a second polymer composition; the regions being distinct and present in the bicomponent filaments in a sheath-core structure or a side-by-side structure; wherein the first polymer composition comprises aramid polymer containing 0.5 to 20 weight percent homogeneously dispersed discrete carbon particles and the second polymer composition comprises aramid polymer being free of discrete carbon particles and having at least one homogeneously dispersed masking pigment, the yarn having a total content of 0.5 to 5 weight percent discrete carbon particles.

Abstract: An improved method for the selective vapor phase oxidation of propylene to acrolein in a recirculating solids reactor system using a bismuth molybdate multimetal oxide involving specific reactant concentrations (preferably 5 mol % to 30 mol % propylene, 0 to 20 mol % oxygen, and the remainder inert gas), particle size (1 to 300 micrometers), temperature (250 to 450° C.) and gas (1 to 15 seconds) and solids (2 to 60 seconds) residence times. Such a process leads to improved selectivity and propylene conversion.

Abstract: An improved method for the selective vapor phase oxidation of acrolein to acrylic acid in a recirculating solids reactor system using a particulate molybdenum vanadate multimetal oxide as oxidant involving specific reactant concentrations (preferably 5 mol % to 30 mol % propylene, 0 to 20 mol % oxygen, 0 to 70 mol % water, and the remainder inert gas), solids particle size (20 to 300 micrometers), temperature (250 to 450° C.) and gas (1 to 15 seconds) and solids (2 to 60 seconds) residence times. Such a process leads to improved selectivity, conversion and solids conversion ratio.

Abstract: An improved method for manufacturing acrylic acid by vapor phase oxidation of propylene in a single step or reaction stage using as solid phase oxidant a mixture of two particulate solids comprising a bismuth molybdate multimetal oxide (e.g., Mo12Co3.5Bi1.1Fe0.8W0.5Si1.4K0.05Ox) and a molybdenum vanadate multimetal oxide (e.g., Mo12V4.8Sr0.5W2.4Cu2.2Ox). Such a process is advantageously carried out in a recirculating solids reactor system wherein the particulate mixture of solids in an oxidized state reacts with a feed gas containing propylene in a vertical riser reactor and after separation from the acrylic acid gaseous product the particulate mixture of solids in a reduced state is regenerated by contact with an oxygen containing gas in a separate regeneration reactor before recirculation to the riser for further reaction.