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The search for more sustainable solutions for plastics production, moving away from petrochemical feedstocks as today's major raw material basis, is a research area of increasing interest. This task goes far beyond the issue of designing greener polymers and their related monomers as tailor-made plastics require, besides the polymer itself, further components. These additives also need to be switched from typically fossilbased to bio-renewable raw materials. One of such necessary components for many applications are plasticizers, and a major application of them is related to polyvinyl chloride (PVC) as one of the leading polymers with a wide range of applications. Typically today's plasticizers are based on fossil feedstocks, and some of them such as specific ortho-phthalates as the most important product class of plasticizers are now subject to restrictions and authorization by the EU's REACH legislation due to their toxicological profile. In this contribution, we report the synthesis and technical evaluation of alternative, novel bicyclic plasticizer candidates, which are fully accessible from renewable feedstocks. In detail, these new plasticizer target molecules are based on the use of the furan-derivative 2-methylfuran, maleic anhydride and 2-ethylhexanol as bio-based starting materials. The synthetic concept consists of an initial Diels-Alder reaction with 2-methylfuran and a subsequent hydrogenation and optional esterification step. The applied reactions are wellknown as economic and sustainable technologies. Thus, not only the starting materials (being of bio-based origin) but also the selected reaction technologies for the syntheses of the target molecules are sustainable. Furthermore, a range of performance tests enabled an insight into structure-performance relationships and revealed promising plasticizing properties of this new bio-based plasticizer generation with, e. g., an attractive solution temperature fulfilling the criterium for a "fast fuser" as well as good compatibility with PVC.

Alternating copolymers from isopropenyl isocyanate and N-substituted maleimides (Nphenyl, N-tetradecyl-and N-octadecylmaleimide) were synthesized for the first time. The reactive copolymers with regular structure have an isocyanate group in the constitutional repeating unit which allows modification and functionalization in a polymer analogous reaction. Functionalization has been demonstrated with examples of amphiphilic copolymers having the hydrophobic and the hydrophilic chain attached to the polymer backbone in a regular alternating fashion. A second example is an alternating copolymer with an NLO-chromophore attached to the polymer.

The free radical copolymerization of the electron rich monomers vinyl isocyanate, isopropenyl isocyanate, trans-I-propenyl isocyanate, and trans-P-styryl isocyanate with maleic anhydride has been investigated. The copolymerization behaviour of different electron deficient monomers like maleic anhydride, citraconic anhydride, N-phenylmaleimide and fumaronitrile with isopropenyl isocyanate or vinyl isocyanate has also been studied. Polymerization in benzene is accompanied by precipitation of polymer, while the polymerization proceeds in solution in 2-butanone. Alternating copolymers were obtained in all cases. The alternating behaviour is favoured by the very low tendency of all monomers except maleimides to undergo homopolymerization. From the reaction with maleic anhydride the reactivity of electron donating monomers was found to be vinyl isocyanate = isopropenyl isocyanate % P-styryl isocyanate = > I-propenyl isocyanate, while the reactivity of electron accepting monomers with isopropenyl isocyanate was: maleic anydride > N-phenylmaleimide > fumaronitrile.

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