The copolymerization equation considering the penultimate unit effect, the so called penultimate model, takes a simplified shape in the case of rz = 0 (monomer 2, M,, does not homopolymerize). For this case a method analogous to the conventional KT(Ke1en-Tiid&transformation for estimation of r , and rl' is proposed. The new method was verified by literature data for the system styrene/fumarodinitrile, polymerized with benzoyl peroxide at 70"C, yielding rl = 0,062 and r,' = 0,812. Classification of copolymerization curves by means of the classical copolymerization model permits to distinguish between three curve-types: rl < 2 (alternation with respect to M3, rl = 2 (linear diagram with slope 0,5) and rl > 2 (non alternating system). The penultimate model permits to generate further curve-types of ''S'khape with r, < 2 and r,' > 2 or rl > 2 and r,' < 2 (rl = rl' for classically behaving systems and r, =k rl' for non-classically behaving systems).

Despite all the technical and economic problems and the public discussions on the environmental dangers and hazards of chlorine chemistry, poly(vinyl chloride) (PVC) is the second most produced plastic (with a worldwide capacity of about 31 million tons), placing after polyolefins and before styrene polymers. Presently, PVC production worldwide is growing at a rate of more than 4% per year. The application of PVC was first described in a patent in 1913, but only after 1930 did a sustained interest in PVC arise in several industrial laboratories. The most remarkable milestones in PVC history and their importance to the development of macromolecular chemistry are briefly described, and some present PVC research and industrial applications, with respect to polymerization, stabilization, bulk property modification, and chemical and material recycling of PVC waste, are discussed. Some actual selected topics include the emulsion polymerization of vinyl chloride with polymeric surfactants and controlled free‐radical polymerization with nitroxyls, whereas ionic and metal organic initiators have not found any technical applications. Chemical reactions offer many possibilities for the modification of PVC, but they have been not used on a technical scale yet. Much work has been done on stabilization with nontoxic or metal‐free systems. The bulk properties of PVC can be influenced by impact modification through the addition of graft copolymers or by blending with other polymers. Also presented are some problems and recent developments in PVC recycling. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 578–586, 2004

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Polymers from 1,4:3,6‐Dianhydrosorbitol 1,4:3,6‐Dianhydrosorbitol and several similar dioles are easily accessible by technical processes. They can be used for the the synthesis of high molecular polyesters, polyurethanes and polycarbonates. The thermal and mechanical properties of the obtained polymers are similar to that of the respective polymers obtained from usual petrochemical raw materials. Also unsaturated polyesters can be prepared and cured by usual methods. Some of the investigated aliphatic polyesters are suitable as polymeric plasticizers for polyvinylchloride. In conclusion, it is therefore possible to replace well known dioles on petrochemical basis by monomers which can be obtained from renewable sources like starch.

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At present worldwide about 45% of the manufactured plastic materials and 40% of synthetic rubber are obtained by free radical polymerization processes. The first free radically synthesized polymers were produced between 1910 and 1930 by initiation with peroxy compounds. In the 1940s the polymerization by redox processes was found independently and simultaneously at IG Farben in Germany and ICI in Great Britain. In the 1950s the systematic investigation of azo compounds as free radical initiators followed. Compounds with labile C–C-bonds were investigated as initiators only in the period from the end of the 1960s until the early 1980s. At about the same time, iniferters with cleavable S–S-bonds were studied in detail. Both these initiator classes can be designated as predecessors for “living” or controlled free radical polymerizations with nitroxyl-mediated polymerizations, reversible addition fragmentation chain transfer processes (RAFT), and atom transfer radical polymerizations (ATRP).

The kinetics of the free radical terpolymerization of diethyl maleate (DEM) (M, ) with methyl methacrylate (MMA) (M2 ) and styrene (M3 ) was investigated at 60 O C with AIBN as initiator. The analysis of the dependence of the terpolymer composition on the feed composition was difficult due to the similar chemical and physical properties of diethyl maleate and methyl methacrylate and also by the low content of the former monomer in the terpolymers. Finally, the terpolymer composition could be determined by means of microanalyses of carbon and hydrogen content. The results of these determinations were confirmed by 13C NMR spectroscopy. The initiation rate constant of AIBN was studied at different feed compositions by means of the inhibition method. For the study of the over-all polymerization kinetics of this ternary system it was necessary to take into account the dependence of the termination rate on the feed composition. It was found that not only the viscosity of the solution, but also the properties of the polymer segment next to the radical site have to be considered. Containing only parameters and constants measured independently from terpolymerization, the kinetic equation obtained described satisfactorily the initial over-all rates.

The polymerization of methyl methacrylate (MMA) was initiated with 1,1,2,2‐tetraphenyl‐1,2‐diphenoxyethane (TPPA), 1,1,2,2‐tetraphenyl‐1,2‐bis(trimethylsiloxy)ethane (TPSA), and 1,1,2,2‐tetraphenyl‐1,2‐dicyanoethane (TPCA). The polymerization with these initiators is characterised by three steps: in the first period oligomers from MMA and initiator radicals are formed by primary radical termination. These telechelics are effective initiators for the further free radical polymerization of MMA. After consumption of the initiator radicals with increasing conversion a normal polymerization occurs.