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Highly chlorinated amine derivatives can be prepared by the high‐temperature chlorination of amines and amine derivatives. Essential for the success of this reaction is an adequate temperature control suited to the constitution of the amines. In many cases the chlorination products achieve stability by cleavage reactions with formation of the imidic acid chloride or isocyanide dichloride grouping. Cyclic compounds are formed under special conditions. The chlorination process described can be used to obtain e.g. polychloroaryl and polychloroalkyl isocyanide dichlorides, polychloroaryl and polychloroalkyl imidic acid chlorides, and polychloroheterocyclic compounds.

Polyurethanes can be tailor-made for a wide range of flexible surface coatings, e.g., for textile substrates and leather; and for a wide variety of adhesives. Polyurethanes give unexcelled performance in almost all of these applications. A prime target of coating textiles with polyurethanes is the achievement of the quality of natural leather. A highly water vapor permeable, but water repellent textile coating has recently become possible using a direct coating process. The application of a micro porous polyurethane film on split leather by a reaction process leads to prime quality leather for shoe uppers. For many years, elastomenc polyurethanes have been the top-ranking adhesives for highly plasticized PVC articles. More recently, polyure thanes have been introduced into the market as structural adhesives, especially for the bonding of automotive body parts. A new principle of heterogeneous cross-linking of polyurethanes which has potential for one-package structural adhesives is pre sented. Aqueous polyurethane dispersions can also be tailor-made for the whole range of two-dimensional applications. They complement the high solids and the powder polyurethane coatings, as well as the solvent-free polyurethane adhesives in the fulfillment of ecological and industrial hygiene requirements.

X-ray methods have been used to investigate the structure of the hard domains in polyurethane elastomers based on trans, trans-dicyclohexylmethane 4,4'-diisocyanate (HMDI) with butanediol as the chain extender. The crystalline hard segments become oriented on stretching the films at room temperature, although the degree of crystallinity remains relatively low. The ordering is improved considerably by annealing the films for several hours at 130-190°C: the fiber diagram contains 25 sharp Bragg reflections which are indexed bya triclinicunit cell with dimensions a=5.1 A, b= 10.2 A, c =37.5 A, a = 115.2", p = 84.9", and y =94.2". The cell contains dimer units of two chains which are probably staggered along the caxis direction in the bcplane. In the samples annealed for shorter periods of time, a second less abundant crystal structure is observed that coexists with the first. This second structure is also triclinic with a more extended fiber repeat of c= 41.3 A and is slowly converted to the contracted form on further annealing. Molecular models show that in the extended form the butanediol units have the all-trans conformation, whereas in the contracted form they probably have the tg'tg-t or tg-tg+t conformations, which have lower potential energies than the all-trans form.The chains in both the extended and the contracted conformations are able to form a network of intermolecular hydrogen bonds, and in this regard the structures are very similar to those reported previously for the analogous diphenylmethane diisocyanate (MD1)-based elastomers. Thus the higher melting points for the HMDI-based hard segments are most likely due to hydrophobic interactions between the dicyclohexyl methanes that are stronger than those between the diphenyl methanes of the MDI-based elastomers.