Abstract: An acrylic fiber useful in the preparation of precursor fibers for the preparation of carbon or graphite fibers contains 93.0-99.4 mol percent acrylonitrile, 0.6-4.0 mol percent of ammonium or amine having a pKb of 5 or less as neutralizing cations for sulfonic and sulfuric acid end groups derived from the initiator and activator and as neutralizing cations for sulfonic acid groups derived from one or more sulfonic acid containing comonomers and 0-3.0 mol percent of one or more comonomers selected from the group consisting of simple acrylate or methacrylate esters, simply vinyl esters, styrene, vinyl chloride and vinylidene chloride, the fiber containing no more than 0.3 mol percent of cations other than ammonium or amine.

Abstract: Water soluble polyamines useful as flocculating agents are prepared by reaction of acrylonitrile polymers in solution with dialkylaminoalkylamines using ammonium polysulfide as catalyst.

Abstract: Acrylonitrile copolymers containing basic comonomers have improved color and color stability when the polymerization is carried out using a catalyst selected from the group consisting of hydrogen peroxide, alkyl and aryl hydroperoxides, acetyl and triacetone peroxides and alkali metal perborates and percarbonates along with an activator selected from the group consisting of 1-thioglycerol, 1-thiosorbitol and thioglycol and the polymerization mixture is quenched with a metal sequestering agent and a compound selected from the group consisting of SO.sub.2, sodium bisulfite and sodium metabisulfite.

Abstract: Water soluble polyamines useful as flocculating agents are prepared by reaction of acrylonitrile polymers in solution with dialkylaminoalkylamines using ammonium polysulfide as catalyst.

Abstract: An acrylic fiber useful in the preparation of precursor fibers for the preparation of carbon or graphite fibers contains 93.0-99.4 mol percent acrylonitrile, 0.6-4.0 mol percent of ammonium or amine having a pKb of 5 or less as neutralizing cations for sulfonate and sulfate end groups derived from the initiator and activator and as neutralizing cations for sulfonate groups derived from one or more sulfonic acid containing comonomers and 0-3.0 mol percent of one or more comonomers selected from the group consisting of simple acrylate or methacrylate esters, simply vinyl esters, styrene, vinyl chloride and vinylidene chloride, the fiber containing no more than 0.3 mol percent of cations other than ammonium or amine.