Eric Hequet

Functionalization of a cotton fabric surface with titania nanosols: applications for self-cleaning and UV-protection properties.

In this study, cotton fabric was successfully modified by titania nanosols prepared by means of the sol-gel process with tetrabutyl orthotitanate [Ti(OC(4)H(9))(4)] as the active ingredient. The cotton fabric was padded with the nanosol solution, dried at 60 degrees C, and cured at 150 degrees C. Scanning electron microscopy showed the presence of a titania film on the fiber surface. The photocatalytic properties of titania-nanosol-treated cotton fabric were investigated. The results showed that stains of coffee and red wine were successfully decomposed by exposure of the stained fabric to UV radiation. Furthermore, titania-nanosol treatment imparted to the cotton fabric a very good protection against UV radiation. The durability of the treatment was investigated by performing repeated home laundering, and the results showed no effect of laundering on the UV-protection efficiency.

Creation of a Set of Reference Material for Cotton Fiber Maturity Measurements

It was the goal of the authors to create a set of reference cottons for maturity measurements. To achieve this they selected 104 cotton bales representing the two principal cultivated species. The vast majority of the bales originated in the USA, but some foreign-grown cotton bales were also selected (Egypt, Uzbekistan, Pakistan, Cameroon, Syria, Benin, and Australia). A representative sample of approximately 30 kg (70 pounds) was taken from each bale. Each sample was homogenized according to the protocol used by the International Cotton Calibration Standard Committee (ICCSC) to produce reference cottons. Eight sub-samples per bale were taken and a minimum of 500 cross-sections per sub-sample were analyzed. A broad range of average values of fiber perimeter and fiber maturity for the 104 bales were obtained. Evaluation of the mathematical and statistical relationships pertinent to maturity and fineness revealed that four critical criteria for adequate calibration standards were met. Therefore, this population of bales constitutes a good base for the calibration of the indirect measurement instruments for maturity and fineness.

Transgenic cotton over-producing spinach sucrose phosphate synthase showed enhanced leaf sucrose synthesis and improved fiber quality under controlled environmental conditions

Prior data indicated that enhanced availability of sucrose, a major product of photosynthesis in source leaves and the carbon source for secondary wall cellulose synthesis in fiber sinks, might improve fiber quality under abiotic stress conditions. To test this hypothesis, a family of transgenic cotton plants (Gossypiumhirsutum cv. Coker 312 elite) was produced that over-expressed spinach sucrose-phosphate synthase (SPS) because of its role in regulation of sucrose synthesis in photosynthetic and heterotrophic tissues. A family of 12 independent transgenic lines was characterized in terms of foreign gene insertion, expression of spinach SPS, production of spinach SPS protein, and development of enhanced extractable Vmax SPS activity in leaf and fiber. Lines with the highest Vmax SPS activity were further characterized in terms of carbon partitioning and fiber quality compared to wild-type and transgenic null controls. Leaves of transgenic SPS over-expressing lines showed higher sucrose:starch ratio and partitioning of 14C to sucrose in preference to starch. In two growth chamber experiments with cool nights, ambient CO2 concentration, and limited light below the canopy, the transgenic line with the highest SPS activity in leaf and fiber had higher fiber micronaire and maturity ratio associated with greater thickness of the cellulosic secondary wall.

Inheritance of fiber quality and lint yield in a chemically mutated population of cotton

The narrow germplasm base of the upland cotton (Gossypium hirsutum L.), grown on the Texas high plains historically, has limited improvement of fiber quality. Chemical mutagenesis and subsequent selection have helped the development of lines with improved fiber quality in cultivars adapted to this region. This study was conducted to determine the inheritance of improvements in fiber quality. M3 lines with divergent fiber properties of micronaire, length, and strength were selected from a population of Paymaster HS 200 treated with 3% v/v ethyl methanesulfonate (EMS) for two hours. The 115 selected lines of M4 and M5 generation were evaluated for fiber quality and lint yield. Regression of the M4 and M5 on the M3 generation, as well as the M5 on the M4 was used to generate narrow sense heritability coefficients. Significant variations were observed between the mutant lines in all generations except for lint yield in the M5 (1997). The highest heritability estimates were found in fiber length (h2= 0.29** to 0.46**). Micronaire and strength showed intermediate heritability estimates of h2= 0.14 to 0.19, while lint yield had a very low heritability estimate of h2= 0.03. Fiber length and strength were correlated (r= 0.58** to 0.46**) in all the three generations. The mutants identified in these studies have the potential to improve fiber quality of upland cotton without introducing alien genes that may reduce adaptation to short growing season production regions.

Relationships of cotton fiber properties to ring-spun yarn quality on selected High Plains cottons:

Cotton fiber properties play an important role in determining spinning performance but explain only a portion of the variability in final yarn quality parameters. This research investigates relationships between ring-spun yarn quality and fiber properties (measured using the High Volume Instrument (HVI) and Advanced Fiber Information System (AFIS)) given additional information on harvest method and cultivar. Seventy-six samples of commercially grown cotton representing five cultivars from six locations across the Texas High Plains were collected over three years. Carded 14.5 tex (40 Ne) ring-spun yarns were produced and tested for various yarn quality characteristics. Principal component analysis and partial least squares regression were used to determine relationships between fiber and yarn properties. Neither harvest method nor cultivar explained a significant portion of yarn quality variability beyond that captured by HVI and AFIS results. Yarn work-to-break was highly correlated to fiber bundle elongation, which is not currently reported in official cotton classing reports.

Development of ‘naked-tufted’ seed coat mutants for potential use in cotton production

Use of chemical mutagenesis has been highly successful in most major crops. The objective of this research was to develop ‘naked-tufted’ seed mutants and to incorporate this genetic trait into cotton to enhance crop quality and reduce processing costs. In 1997, six commercial cultivars were treated with 2.45% v/v ethyl methane sulfonate. In 1999, three M3 plants were identified that had partially naked seed coats. The trait was stabilized through individual plant selections from 2000 to 2004. During 2005 and 2006, the homozygous naked-tufted M8 mutant lines were evaluated for lint yield, lint percent, fibers/seed, fibers/mm2, fiber quality, seed oil content, ginning efficiency and yarn spinning performance. Overall, the naked-tufted seed mutants had lower lint yield, lower fibers/seed, lower lint/seed, and lower fibers/mm2 when compared with their original fuzzy parents. The lint turnout from the mutants was similar to the fuzzy parents and the commercial cultivars. The naked-tufted seed mutants had higher seed oil percent, 6–17% lower short fiber contents, significantly reduced seed coat neps (37–42%), higher elongation and yarn tenacity than their fuzzy counterparts. Preliminary data also showed that the naked-tufted mutants required less energy to gin.

Functionalization of Cotton Fabric with Vinyltrimethoxysilane

The surface of cotton fabric was successfully functionalized with vinyltrimethoxysilane in order to impart water repellency and wrinkle recovery and to introduce surface vinyl groups (—CH=CH2) to the fabric, which could then be initiated for copolymerization reactions with various monomers. The introduction of active groups onto the fabric surface was evidenced from the universal attenuated total reflectance Fourier transform infrared (UATR-FTIR) spectrum of the treated fabric. The spectrum shows two peaks located at 1410 and 1600 cm—1 (C=C stretch). An additional peak located at 756 cm—1 attributed to Si—O—Si symmetric stretch was also observed. Excellent water contact angle and wrinkle recovery angle values were obtained.

Using Fiber Elongation to Improve Genetic Screening in Cotton Breeding Programs

In this study, the bundle elongation and tenacity of cotton fibers were measured using a modified tensile testing instrument to which Pressley clamps (1/8” gage length) were adapted. 32 cotton genotypes with a range of bundle tenacity and elongation were carefully selected based on their distinct physical properties. The work of rupture was calculated from the load vs. elongation curves for each type of cotton. Results demonstrated the importance of fiber bundle elongation in the work of rupture of fiber bundles, which is critically important to processing performance. This study lays a foundation for future efforts to calibrate the high volume instrument elongation measurements and to breed new cultivars with improved work of rupture. This should result in lower fiber breakage when the cotton fibers are submitted to different mechanical stresses (ginning, carding, spinning, and weaving).

Objective Evaluation of Durable Press Treatments and Fabric Smoothness Ratings

In this research, we validate an imaging system for automatic grading of fabric smoothness, developed at Texas Tech University. This system consists of a sheet-of-light, laser-line projector; a smart CMOS camera; a moving platform; and a PC. Its purpose is to provide the textile industry with a tool for rapid, objective evaluation of fabric smoothness after home laundering. The validation study involves two cotton fabrics treated with increasing amounts of a textile-finishing agent to impart durable press properties. The UATR-FTIR is used as a rapid and nondestructive technique to determine the amount of the crosslinking agent linked to the cellulose after the required laundering cycles. To demonstrate the potential of our newly developed imaging system, we extract five features from the acquired images and relate them to AATCC grading and to the amount of finish as evaluated by FTIR. Our results demonstrate that this new wrinkle measurement technology has the potential to discriminate between different levels of fabric treatments and different fabrics.

Evaluation of modern cotton harvest systems on irrigated cotton: fiber quality

Picker and stripper harvest systems were evaluated on production-scale irrigated cotton on the High Plains of Texas over three harvest seasons. Observations on fiber quality using High Volume Instrument (HVI) and Advanced Fiber Information Systems (AFIS) were made on multiple cultivars harvested from six locations. When fibers were relatively immature, micronaire, length, and length uniformity as measured by HVI were better for picker harvested cotton than for stripped cotton leading to a higher loan value and average sale price for the producer. In cases where fibers were more mature, differences in fiber quality parameters between picked and stripped cottons were less pronounced leading to less discrepancy in the value of cotton harvested. However, differences in nep counts, short fiber content, and visible foreign matter between harvest treatments were still distinguishable. The results of this study indicate that producers may realize greater fiber quality and lint value by using picker harvesters, but the magnitude of those differences are a function of growing conditions and/or fiber maturity. Differences in cultivars also played a large role in determining fiber properties.