Reactive intramolecularly crosslinked macromolecules (RICM) (reactive microgels) have been synthesized by emulsion copolymerization. Besides 1,4‐divinylbenzene (1,4‐DVB), self‐emulsifying unsaturated polyesters (EUP) were used. In copolymerization of EUP and comonomers the diffusion rate of the latter influences the copolymerization rate of the growing species, if the initiator concentration is high and the water solubility of the difunctional comonomer is low. The compact structure of RICM is indicated by low slopes of log [\eta]/logw. Values of [\eta] of RICM are low and their molar masses high. [\eta] depends on the structure of RICM, e.g. pendent chains and crosslink density. Structures with pendent EUP chains could be confirmed by hydrolytic degradation. RICM may be stabilized electrostatically or sterically. Network chains of RICM from 1,4‐DVB are immobile.

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Emulsion copolymerization of unsaturated polyesters (UP) with styrene was initiated by potassium peroxodisulfate and by azodiisobutyronitrile (AIBN). The decay rates of both initiators were compared and influences of temperature, electrolyte and concentration of the reaction components studied. Initiation radicals from the persulfate partly add to unsaturated UP units and decarboxylate terminal acid groups of the UP. Initiation by AIBN predominantly occurs in the aqueous phase, and side reactions with this initiator are neglectable.

Selectively deuterated intramolecularly crosslinked macromolecules were studied by dynamic 2H NMR spectroscopy. By performing various relaxation experiments detailed information about the molecular mobility o f the various components of the polymer chains could be obtained. In particular, the NMR investigations revealed significant effects of molar mass or degree of isomerization on the motional characteristics. INTROWCTIONReactive intramolecularly crosslinked macromolecules (RICM) are formed by emulsion copolymerization o f self-emulsifying unsaturated polyesters (EUP) with monomers such as styrene or 1,4-divinylbenzene (DVB).l) In this study, EUP is the crosslinking agent for the monomers and simultaneously the emulsifier.2) The resulting RICM are crosslinked particles of colloidal dimensions exhibiting interesting bulk properties. In previous studies, RICM have been characterized by various techniques including viscosimetry, IRand UV-spectroscopy, electron microscopy, small angle and dynamic light ~cattering.~'~'~) However, so far little is known about the molecular order and internal mobility of the RICM. These molecular properties have an influence on the reactivity of these systems.In this paper, RICM have been studied by solid state 2H NMR techniques, which are well-known and reliable for the evaluation of molecular mobilities.516) In the following we present dynamic *H NMR experiments of various RICM, selectively deuterated either in the EUP or styrene components. The main objective of these studies was to characterize the mobility of the different RICM constituents. 0 1991 Hiithig & Wepf Verlag, Base1 CCC 0003-3146/91/$03.00