IONOMER STUDIES OF POLYETHYLENE ACRYLIC-ACID COPOLYMER .1. FIBER PREPARATION AND PROPERTIES

Two EAA (Ethylene/acrylic acid) copolymers from Dow Chemical Company h ave been studied. Primacor resin (5980), having a mol wt of about 30,0 00 and an acrylic acid content of 19.2%, was converted into 10 and 20 denier per filament fibers to create a high surface area. Cold drawing and use of a fiber lubricant helped prevent sticking and blocking dur ing spinning. The fiber was optimally swollen in a 0.5 N caustic at 55 -degrees-C to produce an ion exchange fiber. Primacor resin (5980) in pellet form was reacted with alkali and was subsequently hammermilled into an ion exchange porous particulate. Physical and chemical propert ies, such as thermal properties, swelling, cation exchange activity an d selectivity, tensile and elongation properties, among others, were d etermined on the fiber before and after conversion to specific metal ( cationic) forms. The swollen fibers appeared to have more cation bindi ng capacity than hammermilled pellets. The EAA polymers were colored b y some metal cations. Some metal cations could be preferentially remov ed from solutions of mixed cations. Most fibers were weak, even after exchanging with multivalent ions, and did not have a precise melting p oint. Fiber tension and solution pH during the cationic exchange had a n effect on the cation uptake, as well as on the physical properties o btained.