The translational diffusion coefficient Do, the sedimentation coefficient So, and the intrinsic viscosity [q] of samples and fractions of poly(1-vinyl-2-pyrrolidone) were measured in a 0.1 M solution of sodium acetate in the molecular weight range 2 Q Ma Q 2200. For M > 4. lo4 the following relationships were obtained: [q] = 8,86-1 0 -5 * d " , Do = 2,42 -M-oss8, and So = 2,14 * lo-" * d-". For M < 4 * lo4 the corresponding relations are [q] = 5,O. 10-4*&s56, Do = 129. 10-4.M-0*s2 and S -1,15 -i0-l' The hydrodynamic invariant is A, = (3,2 f 025). lO-"J -K-' * m~!-"~ and the sedimentation parameter 8, = (i,3 f 0,17) * lo7 m~l -~" . The temperature coefficient of the intrinsic viscosity is negative, viz. Aln[q]/AT = -6.3 * K-'. The evaluation of the length of the Kuhn segment A and the hydrodynamic diameter d of chains representing the molecules of PVP in solution was conducted on the basis of the theory for the hydrodynamic properties of a wormlike necklace taking into account the excluded volume effects. The values of A agree with those obtained from the Burchard-Stockmayer-Fixman and Cowie-Bywater equations, A = (2,l f 0,3) nm and d = (0,5 f 0,13) nm.

Amphiphilic oligomers of poly(N-acryloylmorpholine) terminated at one end by primary amino groups have been prepared by free radical polymerization of the corresponding monomer, N-acryloylmorpholine, in the presence of cysteamine (2-mercaptoethylamine) as chain-transfer agent. The polymerization reaction was performed in aqueous media at acidic pH, in order to avoid any hydrogen-transfer addition reaction the the acrylic double bonds by the SH or NH, groups present in cysteamine. The chain-transfer constant of cysteamine towards N-acryloylmorpholine, under the conditions we used, was found to be very close to 1. The aminated poly(N-acryloylmorpholine) oligomers were found to behave as true macromonomers in polyaddition reactions with a diacrylamide, leading to new poly(amidoamines) carrying poly(N-acryloylmorpholine) chains as side substituents.

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