Textile Research Journal

Physical and mechanical properties of some specific cotton-rich, high tenacity, nylon- core yams and greige fabrics developed for military protective clothing are described. The core yams were produced on a modified ring spinning frame, and the fabrics were woven on a conventional dobby loom. The core yams and the fabrics developed from them contained approximately 70% cotton as cover and 30% high tenacity nylon filament as core. The core yams were about 25% stronger than comparable 70/30 cotton/nylon staple intimate blend or all-cotton yams, and the developmental greige fabrics were over 30% stronger. The developmental fabrics, after special finishing, may provide adequate flame retardancy as well as high strength retention. Properties of the finished fabrics will be reported separately.

Acrylonitrile terpolymer containing 92.7% acrylonitrile, 7% vinyl acetate, and 0.3% sodium methallyl sulphonate was hydrolyzed to degrees of hydrolysis of ∼0.104(T₁B ₁), ∼0.367 (T₁B₂), and ∼0.450 (T ₁B₃), respectively, at 40°C with 5% NaOH. Each of these polymers was blended with the parent terpolymer in a 10:90 ( w/w ) ratio and wet-spun using 45:50 (v/v) dimethyl acetamide : water, varying the spin bath tem perature from 10-60°C. The dope viscosity of the blends increased with the increase in the degree of hydrolysis of the product, which could be attributed to the bulky amide-imide groups. Spinnability was the best in a blend containing T₁B3. After au toclaving, these fibers showed higher tenacity (174 kN·m/kg) and moisture regain (1.8%) compared to the parent fibers (124 kN·m/kg and 1.3%) and other blends. The influence of the bath temperature on the structure of the protofibers was also investigated.

We have developed a laboratory method to simulate the effects of actual consumer wear on upholstery fabrics. We used three soiling conditions, i.e., no soil, Bandy Black research clay, and Bandy Black plus synthetic sebum, on four cotton print upholstery fabrics, and a Taber rotary platform double head abraser to abrade the fabrics after soil application. Least significant differences and Pearson's product moment corre lations indicated that this laboratory test method produced breaking strength and elonga tion values similar to those found in the fabrics exposed to a two-year consumer wear study.

The structure of nonwoven heat-bonded geotextiles is analyzed using a geometrical probability approach. An expression of the pore size distribution of these filters is derived from basic manufacturing parameters. Two experimental techniques used to evaluate fabric opening size—dry sieving of glass beads and hydrodynamic sieving of soils—are investigated and the results compared to the calculated opening size obtained using the pore size distribution equation. Excellent agreement has been found between the calculated opening size and the filtration opening size measured with the hydro dynamic sieving technique.

A simple "hot box" type solar collector has been used to achieve simultaneous desizing, scouring, and bleaching of cotton fabrics using a pad-batch method. Excellent properties have been obtained with a batching time of a mere 1½ hours. We discuss the design and efficiency of the solar oven and the results of the experiments done in it. Our observations clearly demonstrate that the solar energy concentrating device can be conveniently used for fabric preparation.

A derivative technique has been applied to infrared absorption spectrophotometry of ramie in the regions 4000-2500 and 2000-700 cm^-1. The second derivative spectra at different scan speeds and differentiator time constants in these regions have been compared with the absorption (zeroth derivative) spectra. The derivative spectra mea sure the slope or curvature of the absorption contours, facilitate to resolve, and detect absorptions that are unresolvable due either to band overlap or low intensity. This method may thus provide more detailed information on the fine structure of cellulose.

We have investigated the extent of wool hydrolysis in the carbonizing steps of acid izing, delay between acidizing and drying, baking, and delay between baking and neutralizing. We have also examined the roles played by oxygen and sorbed water. We found that wool was hydrolyzed by 5% (w/v) sulfuric acid solution even at room temperature during the delay time between the acidizing and drying steps. The drying of acidized wool can be divided into two stages. In the first stage of drying, the rate of wool hydrolysis changes with drying time, but remains constant in the second stage of drying. We observed critical temperature points at 70°C in drying and at 120°C in baking, above which wool hydrolysis increases significantly. The results suggest that in the absence of water, virtually no wool hydrolysis will occur under acid conditions; however, no amount of drying will curtail wool hydrolysis because of powerful water retention by the sulfuric acid. Oxygen does not appear to play any significant role in wool hydrolysis during carbonizing.

On-line production monitoring of textile manufacturing operations is used increas ingly, but to fully benefit from this trend in automation, the monitored information should be used for real-time decision making. We have investigated the required changes in the more common methods of workload allocation in weaving, and we propose a different approach to workload allocation, called "team weaving." Through a computer simulation of the weave room operations, we have analyzed the advantages of the proposed approach over current practices.