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A ratio of acrylonitrile groups (A) and 1,2‐ and 1,4‐bonded butadiene (B) in SKN‐18, SKN‐26 and SKN‐40 nitrile rubbers has been determined by means of a 250 MHz NMR spectrometer. The amounts of the corresponding units in mol% were as follows: 20; 28; 39 for A and 12; 7‐9; 4‐3 for B1.2. Block‐bonded acrylonitrile has been detected only in SKN‐40 where the ratio of the triad sequences AAB and BAB is 3:97. Quantitative data on the BBB, BBA and ABA triads of 1,4‐butadiene have been obtained by using the signals of the double bond methine protons at 5‐20‐5‐67 ppm. A clearly outlined decreasing trend of the proportion of the Btrans:Btrans sequence with respect to both the Btrans:Bcis and Bcis:Bcis dyads in the order SKN‐18, SKN‐26 and SKN‐40 was found. It was suggested that the signals located in the ‐02‐5‐20ppm region relate to the AB1.2B and probably to the AB1.2A triad sequences.

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A method has been developed for qualitative identification and quantitative determination of linoleic acid mono-and diesters of polyethyleneglycols with various molecular masses. The method is based on proton nuclear magnetic resonance (NMR) spectroscopy analysis of the product obtained after in situ reaction of the ester mixture with trichloroacetyl isocyanate.