The growth of poly (ethylene oxide) (PEO) spherulites was observed synchronously with a polarized optical microscope, which was equipped with a video detector, and so the whole growing process of the PEO spherulites was dynamically recorded as a movie. There was a series of concentric diffractive bands on the surface of the PEO spherulites; furthermore, the diffractive banding did not exist until at least two independent PEO spherulites came into contact with each other. However, the formation of the diffractive banding on the PEO spherulites was also related to the crystallization conditions. It was concluded qualitatively that the diffractive banding formed more easily at the crystallization temperature with a high degree of supercooling, and this was explained in kinetic terms.

In order to investigate the property and concentration dependence of dissociation and hydrolysis of polyelectrolytes, acrylic acid-sodium acrylate copolymers with various degree of neutralization were prepared by adding calculated amounts of sodium hydroxide into the aqueous solutions of a poly(acrylic acid) sample, and the pH values of the solutions covering a wide concentration range were measured for each copolymer at 25℃. It was found that the pH values of the solutions of a copolymer with degree of neutralization of 0.96 kept constant and equaled to 9.80 as c>0.001mol/L. For another copolymer with degree of neutralization of 0.30, the pH values of its solutions remained constant and equaled to 6.25 as c<0.001mol/L. These two copolymers may serve as polymeric buffer reagents which couldn't penetrate through semi-permeable membranes in the corresponding concentration regions.

The effect of solvation-desolvation process on the conformational change of poly(vinyl alcohol) in an extremely dilute aqueous solution during the repeated freezing–thawing treatment was investigated by a differential refractometer. It was found that the hydrodynamic volume of PVA decreased regularly and smoothly with the number of freezing-thawing cycles treatment increasing, as the intra-molecular entanglement points made the polymer chain contract, and even in a full compacted globule state, there were still some solvent molecules in the chain. The extraordinary phenomenon was successfully explained and treated by a quantitative theory in terms of accompanying solvation-desolvation process during the macromolecular chain having contracted.

The special thermosensitive copolymer with lower critical solubility temperature near human heat of 37℃ in aqueous solution has been prepared successfully by copolymerizing N-isopropylacrylamide (NIPAM) and N-isopropylmethacrylamide (NIPMAM) randomly at an appropriate monomer ratio. The self-association behavior of the poly[NIPAM-ran-NIPMAM] copolymer has been studied by dynamic laser light scattering (DLLS) at a concentration higher than the critical concentration of the self-association calculated from viscosity data according to cluster theory. The effect of the concentration and temperature on the self-association behavior in water has been discussed respectively.

Two distinct single-chain particles of poly(N-isopropylacrylamide) (PNIPAM) in the state of loose coil and compact globule, have been prepared successfully below and above the lower critical solution temperature (LCST) in extreme dilute aqueous solution by the freeze-drying method, respectively. During the preparation of the compact globular single-chain sample, the surfactant of sodium n-dodecyl sulfate (SDS) was added into the system to prevent aggregation of globular single chains formed at a temperature above the LCST. After all the coil has been transformed into the compact globular particle, the SDS molecules were removed by dialysis. The glass transition temperature (T g) of the two single-chain samples has been measured by di