The degree of polymerization (DP) and the molecular weight distribution (MWD) play a special role in producing cellulose fiber by using the N-methyl morpholine N-oxide (NMMO) process. In this paper, rheological methods have been used to determine the MWD of cellulose. It is shown that the limiting compliance J⁰_e of cellulose samples increases strongly with the increasing broadness of MWD, and that the polydispersity index ‹τ_W›/‹τ_N› of the distribution of relaxation times can also well characterize the polydispersity of MWD of the cellulose samples. By using Tuminello's method, the cumulative weight distribution C(M) can be calculated from the terminal modulus and the plateau modulus of the cellulose/NMMO solution via 1-[G'(ω)/and G⁰_N]^0.5 (G'(ω) and G⁰_N are the storage modulus and the plateau modulus respectively).

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Interaction of polyamide 6 fibres with some organic compounds vis. phenol, ethanolamine, ethylamine, and formaldehyde was thoroughly investigated. Some changes in the internal polymer fine structure as well as in the fibre mechanical properties were attained. Characterisations of the modified substrates were performed through measurements of the dynamic length shrinkage, change in weight, differential thermal analysis, x-ray diffraction, thermogravimetric, viscosity analyses and dyeability. The treatment revealed a decrease in the glass transition temperature, change in crystallinity, d-spacing and crystal perfection index. Dyeability with acid and disperse dyestuffs was also progressively increased.

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Effect of crystallization on damping properties of organic hybrid prepared from a mixture of chlorinated polyethylene (CPE) / N, N’-dicyclohexyl-2-benzothiazolylsulfenamide (DBS) was investigated. The as-produced mixture were annealed at 25°C, 60°C and 80°C respectively, for different period so as experience the different crystallization history. DSC measurement as well as SEM observation showed that the crystallization can be accelerated by increasing the annealing temperature; meanwhile, the melting process becomes narrow and the melting peak point shifts to higher temperatures. As a consequence of the great change in crystalline morphology, both the storage modulus and the loss modulus in glass transition changes remarkably, indicating that the damping properties of the organic hybrid might be controlled through the control of crystallization history. Further studies by Energy-Dispersive X-ray Spectrometry (EDX) revealed that there exists a supramolecular organization between CPE and DBS even in the crystalline domains. The organic hybrid with such kind of architecture results in the good damping behavior which is definitely different from that of inorganic/polymer composition.

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The lignin-based polymers (lignophenols) were synthesized through the phase-separation system composed of the concentrated acid and p-alkylphenols. The relationship between the structures of phenols constituting the organic phase and functionalization effects of lignin in the phase-separation reaction was discussed. The lignin functionalization rate got lower with the extension of alkyl substituents on phenolic nuclei, due to the hydrophobicity and steric hindrance of alkyl substituents. The depolymerizations of lignophenols were the participation of C1-phenolic nuclei in alkaline media. Both spruce and maple lignophenols were effectively depolymerized by the treatment with 0.5N NaOH at 120°C to 170°C. There was a good correlation between the frequency of grafted phenolic nuclei and the depolymerization degree of lignophenols, independent of the structures of grafted phenols.

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Polyester / Cotton (50/50, 65/35) fabrics were treated with liquid ammonia under practical conditions, followed by resin-finishing with nitrogen-contained glyoxal resin NS-19 (Sumitomo Chemical Co.). Nitrogen content, washing shrinkage, crease recovery angle, softness, and KES shearing and bending properties were measured. Nitrogen content of the NH₃ treated cotton fabric after resin treatment is obviously decreased as the same behavior in dyeing with CI Direct Blue 1. Although washing shrinkage and crease recovery were diminished with the NH₃ treatment, the shrinkage and crease recovery were decreased much more with an increase of polyester fiber content. KES shearing and bending parameters are also decreased with the NH₃ treatment.

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