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Nitrile groups of poly(styrene‐co‐acrylonitrile) (SAN) can be converted to 2‐substituted Δ2‐oxazoline using 2‐aminoethanol. The formation of oxazoline in SAN can be significantly increased through addition of substituted aminoalcohols like 2‐amino‐2‐ethylpropane‐1,3‐diol and 2‐aminobutanol and through reaction with 3‐aminopropanol using dibutyltin oxide as catalyst. Using this procedure, dihydro‐4H‐oxazine can be easily produced from 3‐aminopropanol due to the lower ring tension in comparison with the five‐membered oxazoline ring.

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A good way of achieving compatibility in polymer blends of poly(styrene-co-acrylonitrile) (S/AN) and bisphenol A polycarbonate (PC) is the chemical modification of S/AN in the melt. A catalyzed reaction of the nitrile groups with a substituted 2-amino alcohol or 2-amino phenol resulted in a conversion of nitrile groups of 55-75% in 60 min. The introduced heterocyclic structures were ethyl hydroxymethyl oxazoline (EHMOXA) and benzoxazole (Benz-OXA), respectively. The use of dibutyltin oxide as a catalyst led to the highest efficiency. The modified polymer was characterized by Fourier transform infrared and NMR spectroscopy, elemental analysis, and reactions with organic acids and anhydrides. The modified S/AN showed good technical compatibility (single glass-transition temperature) with PC in blends made from solution and from the melt. All blends were characterized with oscillating rheometry and differential scanning calorimetry. Rheological measurements showed that EHMOXA-S/AN reacted with PC and had crosslinked structures, whereas BenzOXA-S/AN showed compatibilization without any (crosslinking) reaction. The melt blends of BenzOXA-S/AN and PC showed a downward shift in the complex viscosity due to the influence of the BenzOXA group.

The polymer micro structure of poly(butene‐1) can be designed by the introduction of comonomers like ethylene (poly(ethylene‐co‐butene‐1)) as well as the dedicated use of special polymerization catalysts. With the use of ethylene as comonomer the change of polymer micro structure also leads to changes in the macroscopic material parameters leading to polymers with a new application profile which are of special interest as hot melt adhesive raw materials. The use of dedicated polymerization catalysts allows the production of new poly(butene‐1) hot melt adhesive raw materials without the use of additional comonomers.