No abstract

Homopolymerization of acrylamide (AAM) as well as of methyl methacrylate (MMA) in inverse microemulsions was studied and compared with the homopolymerization of these monomers in homogeneous systems. Initiators with various solubilities in water were used. Homopolymerization of AAM in inverse microemulsion was found to be an extremely fast reaction independent of the type of the initiator used. It is .awned that polymerization takes place predominantly in the interlayer between the aqueous phase and the oil phase In the case of MMA the homopolymerization in inverse emulsion is a relatively slow process. It is assumed that polymerization of MMA in the systems studied takes place in the oil macrophase Experimental partChemicuk Acrylamide (AAM). product of SERVA (Germany) was used without purification. Methyl methacrylate (MMA) and/or styrene (S), product of CHZ Zilina (Czechoslovakia) were deprived of inhibitor before use and distilled under nitrogen at reduced pressure 2,2'-Azoisobutyronitrile (AIBN), product of Fluka (Switzerland) was crystallbed from methanol before use. similarly as dibenzoyl peroxide (BP), pure (Fluka). Ammonium peroxodisulfate, pure (APS), Lachema Brno (Czechoslovakia) was used without purification. NJVflfl-tetramethylethylenediamine (TMDA), pure (SERVA) was used without purification. The polymerization medium was ' )

The copolymerization of acrylamide with methyl methacrylate or styrene in inverse microemulsion initiated by radical initiators with different solubility in water was studied in the initial stages of the reaction. It was found that the initial rate of copolymerization depends on the mole fraction of acrylamide in the comonomer mixture and is independent of the solubility of the radical initiator in water. Experimental partChemicals: Acrylamide (AAM), product of Serva Heidelberg, Germany was used without purification. Methyl methacrylate (MMA) and styrene (St), products of CHZ Zilina, Czechoslovakia, were deprived of inhibitor and distilled at reduced pressure in a nitrogen stream a) Part 2: cf.@. b, Revised manuscript of October 29, 1990. 0 1991, Hiithig & Wepf Verlag, Base1 CCC 0025-1 16)3/91/$03.00 1340V. VaikovB, V. JuraniEova, J. Bartoh before use. 2,2'-Azoisobutyronitrile (AIBN) and dibenzoyl peroxide (BP), products of Fluka, AG, Buchs, Switzerland were recrystallized from methanol before use. Ammonium peroxodisulfate (APS), pure, product of Lachema, Brno, Czechoslovakia was used without purification. Emulsifier sodium bis(2-ethylhexy1)sulfosuccinate (Am), product of Fluka containing a maximum of 3% humidity was used without purification. The polymerization medium consisted of distilled water, cooled after boiling in a stream of argon (1 wt. portion) and of toluene (anal. grade) from Lachema (10 wt. portions). Procedures:The polymerizations were performed as described elsewhere ', *). The conversion determined after 5,5 min was used to establish the initial copolymerization rate. The composition of the products was determined using elemental analysis (WC Heraeus elemental analysis device). Absorption spectra of solid samples in the infrared region were measured on the Perkin-Elmer G 983 Spectrophotometer; the KBr technique was used.