The liquid‐crystalline properties of three cellulose esters, phenylacetoxy cellulose (PAC), 4‐methoxyphenylacetoxy cellulose (4MPAC), and p‐tolylacetoxy cellulose (TAC) and two cellulose silyl ethers, trimethyl silyl cellulose (TMSC) and t‐butyldimethylsilyl cellulose (TBDMSC), are reported. Hot‐stage polarized light microscopy provided evidence regarding the formation of thermotropic mesophases in the PAC, 4MPAC, TAC, and TMSC in bulk form upon heating. The concomitant DSC data showed further evidence of the thermotropic nature of these materials. PAC, 4MPAC, TAC, and TMSC formed lyotropic mesophases at 44, 48, 50, and 27 wt%, respectively in CH2Cl2. The presence of fingerprint patterns in wholly anisotropic solutions in conjunction with optical rotation measurements confirmed the cholesteric nature of these liquid crystalline solutions. TBDMSC formed neither a lyotropic nor a thermotropic liquid‐crystalline phase due to the low degree of substitution (DS 0.68) of this derivative. The hydroxyl substituents of PAC, 4MPAC, TAC, and TMSC may be readily removed under mild conditions to regenerate cellulose.

In this paper we consider the wide-angle x-ray diffraction patterns of several nylon 66-polyethylene glycol (PEG) blend fibers before and after aqueous extraction. Antistatic additives such as PEG are frequently found in polyamide fibers. The patent literature indicates, however, that fiber blend systems of this type must be extracted in order to function effectively as antistatic fibers.'**The fibers examined in this study were prepared by an industrial laboratory by melt spinning mixtures of PEG and nylon 66 polymer chip. The samples ranged in composition from 0-20% PEG by weight in increments of 5%. The PEG had a molecular weight of ca. 20,000 (Union Carbide Corporation's polyethylene glycol compound 20M). After melt spinning, each blend was drawn to the same draw ratio of approximately 5X. Samples of each blend were extracted in an aqueous solution containing 10 ghiter of Oryus-AB detergent (Proctor and Gamble) for 3 hr at 7OoC and then dried in hot air at 7OoC for 2 hr. All samples containing PEG additive show a significant increase in electrical cond~ctivity.~The wide-angle pattern of the 100% unextracted nylon 66 fiber sample is shown in Figure 1. This structure has been completely analyzed by Bunn and Gardner.' The x-ray pattern of extracted samples of nylon 66 is practically unchanged except the major reflection peaks on the equator are somewhat sharper. The extraction process induces changes approximately equivalent to an annealing treatment of 200OC for 1 min.

Two theoretical models are presented to predict average molecular orientation properties of spider silk which has unknown molecular orientation and chemical structure. Birefringence and elongation (or shrinkage) data are required for two distinct lengths of a sample in order to fit the data. The first model is based on the assumptions that each molecule behaves as the average and that the deformations are affine. The second model is based on a random distribution of the molecules as the fiber is first formed and that the molecular deformations are affine when the fiber is elongated to any length. Data were taken from spider silks in the natural state and in a shrunken state (due to water). The second model gives a much better fit of the data. The models are applicable to other systems.

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Fine dusts in trash samples collected on Pneumafil filter during carding of washed cottons were separated into 20 to 38-μm and <20-μm fractions, their ash contents determined, and elemental analyses performed on the resulting inorganic residues. The quantity of fine dusts separated was affected by carding rate and the use of an electrostatic eliminator on the card. The lower the carding speed, the lower the fine dust content per bale. The electrostatic eliminator significantly increased the amount of fine dusts per bale even at the lowest carding speed. Ash contents varied with washing conditions, carding rate, and whether the electrostatic eliminator was employed. A wide variety of elements was present in the fine dusts, but unexpectedly high levels of Cu, Zn, Fe, and Al were found, which indicate contamination of these cottons.