bands at 3260 cm™1 (NH), 1122 cm™1 (C-N) and 784 cm™1, which are attributable to the polyethylenimine structure.8 The nmr spectrum of the polymer taken in CDCI3 (Figure 7a) shows peaks at r 4.65, 5.03, and 8.03 due to the protons of polybutadiene and peaks at 7.27 and 7.94, which are assignable to IV-methylene protons ((-CHglzN-) and amine proton (>NH), respectively. D20 treatment of the nmr sample solution decreased the com-(8) T. Saegusa, H. Ikeda, and H. Fujii, Macromolecules, 5,108 (1972).bined areas of the peaks at 7.8-8.2. The decrease corresponded to the number of the secondary amine proton. This observation is taken to confirm the structure of the block copolymer (Figure 7b). The peak intensity ratio of IV-methylene protons to amine proton is 4:1. No peak due to amide structure (-CH2N(HCO)CH2-) was observed in the spectrum, which shows complete hydrolysis. These results indicate that the product of the alkaline hydrolysis is an ABA-type block copolymer (VI) with El block (A) and V H0-^CH,CH2Nj-4CH2CH-W-NCH2CH2^-OH ' \ CH=CH2/m VI BD block (B). The El unit content in the block copolymer (VI) was found to be 63 mol % by nmr. This value was in good agreement with that of OXZ-BD block copolymer (61 mol %). The molecular weight of polyEI block was calculated to be 4700 (/ + ~109 in VI). The degree of polymerization of polyEI block agreed fairly well with that of polyOXZ block before hydrolysis.
Polyoxazoline having a terminal triethoxysilyl group was successfully synthesized by the ringopening polymerization of 2-methyl-2-oxazoline followed by termination with (3-aminopropyl)triethoxysilane. Triethoxysilyl-terminated telechelic polyoxazoline was prepared by using a bifunctional initiator. Furthermore, polyoxazolines having two or three triethoxysilyl groups were prepared by using diallylamine as a terminator followed by a hydroeilation reaction with triethoxysilane. These triethoxysilyl-terminated polyoxazolines were subjected to acid-catalyzed cohydrolysis polymerization with tetraethoxysilane by the so-called sol-gel method to produce a novel organic-inorganic polymer hybrid, which was a homogeneous transparent glassy composite material. The obtained hybrid showed a higher hydrophilic property in comparison with that of silica gel without polyoxazoline segments.
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