Rheological properties of two cellulose derivative solutions which exhibit liquid crystalline behavior under certain conditions were determined by using a capillary rheometer. Measurements included the concentration dependence of die swell and shear viscosity for the two solutions of hydroxypropyl cellulose (HPC) in dimethylacetamide and in dimethylsulfoxide. The die swell for both the systems exhibits a maximum and a minimum with respect to polymer concentration. The concentration at the maximum or the minimum is almost identical to that for the shear viscosity. A first normal stress difference N₁ was converted from the die swell data on the basis of the theory which has been applied successfully to isotropic solutions and melts. The concentration dependence of the N₁ converted is qualitatively similar to that reported by other investigators. The values of the die swell for lyotropic liquid crystals may be not so low as those for thermotorpic liquid crystals. This phenomenon may be attributed to the difference of a relaxation time between them.

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In the electron microscopy of parallel arrays of negatively stained cellulose protofibrils the image contrast changes dramatically with the focal setting (defocus) of the objective lens, especially in the lateral direction. In order to facilitate interpretation of the electron micrographs, the linear transfer theory of microscope imaging was used to produce one-dimensional simulated images based on a periodic step model, corresponding to an alternating sequence of negative stain and protofibril domains. For the specimen in question, it is shown that: (1) the first order approximation is effectively valid in image simulation; (2) certain envelope functions, which serve as damping factors on the contrast transfer function, are very important; (3) a small amount of absorption is effective in simulating the image contrast. These results define the factors that must be taken into consideration for calculating the two-dimensional image contrast of negatively stained cellulose protofibrils.

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The fatigue strength in thermoplastic polymers is affected remarkably by temperature. The effects of temperature on the fatigue strength of some thermoplastic polymers such as poly (methyl methacrylate) (PMMA), polyoxymethylene (POM), polyethylene (PE), poly (vinyl chloride) (PVC), polystyrene (PS) and acrylonitrile-butadiene-styrene copolymer (ABS) have been investigated with the change of rise of surface temperature by the fatigue, alternating stress amplitude-number of cycles (S-N) curves and tensile stress-strain (S-S) curves.
The change of fatigue strength of thermoplastic polymers with temperature may be indicated with one curve which has a certain transition temperature and the fatigue fracture in thermoplastic polymers may be roughly divided into three type as thermal fracture which breaks with the rise of temperature, cracking fracture which does not depend on the rise of temperature and the mixed fracture. PMMA is thermal fracture-type, ABS and PS are cracking fracture-type and POM, PE and PVC are the mixed fracture-type at -20°C_??_60°C.

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Acetylation with the conventional method does not confer thermofluidity to wood. However, wood acetylated by the trifluoroacetic anhydride-acetic acid medium (TFAA method) shows an apparent melting behavior at around 300°C. In this case, action of trifluoroacetic acid (TFA) as an agent for effectively cleaving some of the lignin's intramolecular bonding can be postulated. Based on these finding, a kind of simulation of the TFAA method has been attempted. That is, in order to confer thermoplasticity to acetylated wood, acetic acid used in the conventional pretreatment has been replaced by TFA. By using TFA as pretreatment agent and employing other adequate conditions for the pretreatment, acetylated wood with thermofluidity was able to be obtained. This acetylation method is basically a conventional one except the pretreatment. What is more interesting is that the acetylated wood thus obtained shows an apparent melting temperature of about 210°C. This temperature is about 90°C lower than the known apparent melting temperature (flow temperature) of cellulose acetate. The low flow temperature of the wood acetylated after the TFA-containing pretreatment can be experimentally attributed to plasticization of cellulose acetate by acetylated lignin within the acetylated wood.

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Cross-linked polymers consisting of cellulose and polyethyleneimine (PEI) were synthesized by the reaction of reactive cellulose derivatives such as chlorinated cellulose (Cell-Cl), cellulose tosylate (Cell-OTs) and cellulose acetate bromoacetate (AcCell-AcBr) with PEI. With Cell-Cl the reaction easily occurred in DMF and dioxane but was depressed by water contained in the medium. PEI content of the polymers increased with an increase in reaction temperature and with chlorine content in Cell-Cl. Cell-OTs also easily reacted with PEI to give the high PEI content polymers irrespective of reaction temperature and the molecular weight of PEI. AcCell-AcBr gave the products of high PEI content only by the reaction with PEI of high molecular weight. Thermogravimetric analysis suggested that the products were the cross-linked polymers composed of cellulose derivatives and PEI owing to their high thermal stabilities.

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Immobilization of invertase on cross-linked polymers consisting of cellulose and polyethyleneimine (Cell-PEI) and the enzymic activity of immobilized invertase were investigated. Invertase was coupled with Cell-PEI by glutalaldehyde. The amount of invertase coupled was independent of reaction temperature and increased with an increase in invertase concentration. Neutral or weak basic conditions were favorable for the coupling reaction.
The optimum pH of invertase activity was shifted to acidic side by the immobilization. The activity at the optimum pH was 26% of that of native invertase. The optimum temperature of invertase activity was little affected by the immobilization. The immobilized invertase was repeatedly used without the activity loss.

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Dry-rubbing tests on several dyes have been carried out and the effect of soaping on the rubfastness has been investigated from the kinetic viewpoint.
The removal process of dyes can be treated as a reversible reaction of first order. The amount of dye (x) removed from dyed fabric to white cloth after t times of rubbings can be expressed as
where A, k₁, k_-1, K and F are initial dye content on dyed fabric, the rate constant of transfer of dye from dyed fabric to white cloth, the rate constant of reverse process of k₁, equilibrium constant and a constant indicating initial condition, respectively. Values of F become small by soaping for vat or naphthol dyes and in many cases they become zero within an error range. The effects of soaping on the values of x are represented by the kinetic properties. From these kinetic considerations, it has been concluded that soaping effect on the rub-fastness for vat and naphthol dyes is different from that for reactive dyes.
Linear relations have been obtained between _??_nK and the reciprocal of weights (1/W) on the white cloth. The slopes of the straight lines for all of the dyes are roughly equal and they are invariant by soaping.
Relations between _??_nk₁ and 1/W are roughly linear and the slopes of the straight lines for vat and naphthol dyes tend to become large by soaping.

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The contribution of the nonpolar groups in 1-amino-4-alkylaminoanthraquinone-2-sulfonic acids (AAS-R Dyes, R: alkyl=methyl, ethyl, n-propyl, and n-butyl) to the adsorption on 6-nylon having 5.35×10^-5 eq/g amino end group at 70, 80, and 90°C has been studied. The adsorption isotherms of AAS-R Dyes for nylon followed Langmuir's adsorption equation. The affinities of AAS-R Dyes for nylon were calculated by the usual method, and were found to be dependent upon the alkyl groups in the Dyes. The affinities increased with increasing length in alkyl groups by 0.1 to 0.3kcal/mol per methylene group. The adsorption of AAS-R Dye on nylon decreased the heat content and increased entropy of the system.

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