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Aminimides 715 this shift is -0.7 kcal for la and -2.0 kcal for lb. These shifts were reduced to 0.0 for poly(vinylbenzophenone) and -0.7 for Lb when the spectra were recorded from their films, where all of the spectra are about 1-2 kcal lower than in organic glasses.Quantum yields for the sensitized photoisomerization of cis-and frans-stilbene were measured in degassed benzene solutions using light of 366-nm wavelength. The results for the monomeric models have been reported elsewhere.6 The results for the polymeric sensitizers are reported in Table III along with a summary of the monomer values. These results show that the polymers poly(vinylbenzophenone) and poly(/3naphth oylstyrene) sensitize the isomerization of stilbene with the same efficiency as do the corresponding models. However, poly(a-naphthoylstyrene) is less efficient than are its corresponding models in the case of the trans -» cis process. Furthermore, the inefficiency for the anaphthoyl polymer is related to the chain length of the polymer. Thus, when polystyrene of molecular weight 4700 was treated with -naphthoyl chloride, the resultant polymer had a of 0.45 ± 0.01 while the polymer prepared by naphthoylation of a polystyrene with molecular weight 900 had 4 of 0.49 ± 0.01.The inefficiency of the -naphthoylated polymers in sensitizing the trans -* cis isomerization of stilbene could be explained on the basis of the steric requirements of the -naphthoyl group. Such steric requirements could force the polymer into a configuration which would bury the internal chromophores and make them inaccessible to acceptor molecules. However, is normal for poly(a-naphthoylstyrene) and this implies that all of the excitation energy in this polymer is available for sensitization. Thus, it appears that 1

Some representative examples of a new family of aminimide monomers, i.e., trialkylamine N‐acryloyl or N‐methacryloyl glycinimides and β‐aminopropanimides have been prepared and studied. These are the first examples of a possible large family of primary aminimide monomers. With radical initiators, the acryloyl and monosubstituted methacryloyl monomers readily homopolymerize. The disubstituted methacryloyl aminimides do not homopolymerize under the same conditions. All of the new monomers copolymerize with styrene, methyl methacrylate, and n‐butyl acrylate. The various polymers were characterized by IR, DTA, TGA, GPC and inherent viscosities. When heated (160°C) the polymers liberate amine and crosslink in the presence of active hydrogen moieties to give resins with carbamate, urea, allophonate, etc., residues. When no active hydrogens are available during heating, polymers can be prepared with pendent primary isocyanate groups. This preliminary work shows these monomers to be highly useful for preparing a wide variety of reactive copolymers.

Aminimides were prepared from esters of stearic, oleic, linoleic, phenylstearic, 9,10‐dihydroxystearic, ricinoleic and dimer acids. Thermolysis of the aminimides to isocyanates was carried out in a wiped film molecular still and by vacuum distillation of a bulk sample. The latter process is suitable only for small samples of the simple aminimides. Acyl N,N‐dimethylhydrazides, which are aminimide precursors, can generally be prepared by dehydration of carboxylic acid‐unsym‐dimethylhydrazine mixtures. Details of the preparation of dimer acid diisocyanate by this route are presented. Some information on the use of long chain aminimides as emulsifiers for halocarbon mixtures, e.g., bromoform‐water, is presented.

Trimethylamine‐4‐vinylbenzimide (TAVBI) has been homo‐ and copolymerized with styrene, methyl methacrylate, and hydroxypropyl methacrylate by free‐radical initiators to soluble, low molecular weight polymers containing pendant aminimide groups along the backbone of the polymer molecules. The reactivity ratios in the copolymerization of TAVBI (M1) with styrene (M2) were determined: r1 = 0.63 ± 0.07, r2 = 0.47 ± 0.05. The Alfrey‐Price Q and e values for TAVBI were also calculated: Q = 0.88, e = 0.31. This introductory work indicates that TAVBI has potential for the preparation of a wide variety of reactive polymers.