Rayon Samples Research Articles

Evaluation of the OpTest Fiber Quality Analyzer for Quantifying Cotton and Rayon Microfibers

Microfibers are small fiber particles that separate from larger textiles through wear abrasion or home laundering. Pervasive accumulation of synthetic microfibers in the environment is motivating efforts to quantify them, and to gain a better understanding of the factors that lead to their release from garments. Automated imaging systems have been previously employed for the quantification of synthetic and natural microfibers. In the current study, a rayon standard and microfibers sourced from scoured cotton HVI calibration standards were examined with the Fiber Quality Analyzer-360 (FQA) automated imaging system. Mechanically stirred suspensions of six cotton microfiber standards showed significantly lower fiber counts than those obtained with a rayon standard. Probe sonication of the sample suspensions significantly increased observed fiber counts for the cotton standard samples, by 105% on average. Mean length determinations decreased by, on average, 5% for the sonicated samples, an indication that count increases were not due to sample fragmentation. No significant change was observed for the fiber counts or length measurements of the sonicated rayon samples. The sonicated cotton samples showed an average of 95% detection by the FQA. These results highlight the importance of proper microfiber suspension for accurate detection and quantification using the FQA system.

Aerobic biodegradation in freshwater and marine environments of textile microfibers generated in clothes laundering: Effects of cellulose and polyester-based microfibers on the microbiome

The aerobic biodegradation of common textiles that shed microfibers during laundering was evaluated under the action of microbes found in the environment, such as lake and seawater, and activated sludge at a low concentration from a wastewater treatment plant (WWTP). Under these conditions, the biodegradation potential was the same in all the experiments: Microcrystalline Cellulose (MCC) > Cotton > Rayon > Polyester/Cotton ≫ Polyester. Nevertheless, for cotton and rayon yarns, >70% biodegradation was achieved with activated sludge at low concentration and lake water, whereas in seawater, about 50% degradation was reached. Polyester did not appreciably degrade. The biodegradation results herein indicate potential not absolutes in nature. The bacterial diversity analyses in the different biodegradation inoculums show that there are distinct bacterial communities related to the assimilation and mineralization of complex carbohydrates that were promoted with the cellulosic MCC, cotton, and rayon samples different than the polyester sample.

Rapid, Non-Destructive, Textile Classification Using SIMCA on Diffuse Near-Infrared Reflectance Spectra

Soft independent modeling of class analogy (SIMCA) was successful in classifying a large library of 758 commercially available, non-blended samples of acetate, cotton, polyester, rayon, silk and wool 89% - 98% of the time at the 95% confidence level (p = 0.05 significance level). In the present study, cotton and silk had a 62% and 24% chance, respectively, of being classified with their own group and also with rayon. SIMCA correctly identified a counterfeit “silk” sample as polyester. When coupled with diffuse NIR reflectance spectroscopy and a large sample library, SIMCA shows considerable promise as a quick, non-destructive, multivariate method for fiber identification. A major advantage is simplicity. No sample pretreatment of any kind was required, and no adjust-ments were made for fiber origin, manufacturing process residues, topical finishes, weave pattern, or dye content. Increasing the sample library should make the models more robust and improve identification rates over those reported in this paper.

중량변화에 의한 폴리에스터 레이온 부직포의 정전기 대전 완화특성

Non-wovens polyester rayon samples were manufactured, and the electrification properties of electrostatics were measured for three different samples (15 g/, 25 g/, and 40 g/) with the environmental settings of temperature (20~40) and humidity (40~90%). The conclusions are as follows. Heavy sample generated more static electricity when the temperature was constant. The static electricity decreased slowly when the humidity is less than 70%, while it sharply decreased over 70% humidity condition. For non-woven polyester rayon, static charge decreased as temperature and humidity increased. As the weight increased, less time were taken for the electrification voltage to drop to the half.

A comparative study of regenerated bamboo, cotton and viscose rayon fabrics. Part 2: antimicrobial properties

Since regenerated bamboo fibres (also referred to as bamboo viscose) became commercially available in 2006, consumers have been bombarded with contradictory information regarding products made of these fibres, their potential end-uses and their properties. On the one hand, manufacturers and marketers make broad claims about the antimicrobial and environmentally friendly characteristics of products made of regenerated bamboo, while, on the other hand, there is an outcry from consumer watchdogs that many of these claims are false and have not been properly proven. Very little information is available about the validation of these properties through scientific research studies. It is also evident that information about natural bamboo and regenerated bamboo fibre products is often confusing. Regenerated bamboo (also referred to as bamboo viscose or bamboo rayon) is manufactured from natural bamboo fibres in a regeneration process by which bamboo pulp is refined from the stems of the bamboo plant in a process similar to that used to manufacture viscose rayon fibres. The severity of this process has led to scepticism as to whether the antimicrobial properties of the bamboo kun remain unchanged in regenerated bamboo fibres. The question has been raised as to whether residual chemicals on the spun fibres could be the cause of antimicrobial properties. The main objective of this study was to investigate the claim that regenerated bamboo fibres have inherent antimicrobial properties as a result of the bamboo kun present in the raw material from which the fibres are regenerated. For this purpose, the antimicrobial properties of regenerated bamboo fabric were compared to those of viscose rayon and cotton fabrics. The results confirmed that cotton fabric (used as a control) exhibited no antimicrobial activity. However, the antimicrobial effect of the regenerated bamboo and viscose rayon samples was significantly higher than that of the cotton sample, for both Gram-positive bacteria and Gram-negative bacteria. The claims made concerning the bacteriostatic or antimicrobial properties of regenerated bamboo could thus not be proven as false. Statistically, the regenerated bamboo fabrics did not perform better than the viscose rayon fabrics in our tests and did not kill all the bacteria in the solution. No evidence was found that regenerated bamboo fibre fabrics are superior to other regenerated cellulose fibres such as viscose rayon, nor that the antimicrobial properties of natural bamboo remain unchanged in regenerated bamboo fibres.

Colorfastness to Light of Decorative Japanese Book Cloths

The American National Standards Institute and the National Association of State Textbook Administrators have established standards for certain types of book cloths, but there are many fabrics being produced for book covers that are not addressed by these standards. These outlying cloths are more decorative and are being used widely by artists and hand bookbinders working in small editions. Twelve samples of rayon and rayon/acetate Japanese book cloths were selected from available World Cloth Japanese book cloths and tested for colorfastness to light. The specimens were evaluated visually and instrumentally at 24, 48, 72, and 96 hours of exposure. The color changes occurred steadily over the accelerated 96-hour exposure time. The sample book cloths rated poorly in the study, with only one passing established visual and instrumental minimums beyond 24 hours of exposure. This may indicate that when placed in an environment in which light is a regular factor (e.g., a shelf or display case) color change and fading could go undetected until an unwanted transformation had occurred.

Hydrogen bonding on accessible surfaces of cellulose from various sources and relationship to order within crystalline regions

AbstractCelluloses from a variety of common sources were analyzed for availabilities of O(2)H, O(3)H, and O(6)H in order to estimate the extent of hydrogen bonding on accessible fibrillar surfaces. Celluloses from flax, ramie, sisal, and wood (both cellulose I and II from wood) together with liquid NH3‐swollen cotton and NaOH‐swollen cotton (cellulose II) had relative availabilities similar to those of native cotton. Celluloses from Valonia centricosa and in rayon samples stood apart from each other and from the “cotton family.” The difference between Valonia and cotton celluloses appears to result, in addition to the accepted smaller, less perfect crystallites in cotton, from an O(2)H hydrogen bond which is likely the intramolecular bond between O(2)H and O(6′)H that is present in Valonia and absent in cotton. Rayon samples also showed evidence of similar bonds involving O(2)H on accessible surfaces. Since the regenerated rayons had relative availabilities different from those of mercerized cotton and wood cellulose samples, it is proposed that chain packing arrangements are not the same in these two types of cellulose II.

Effects of tampon materials on the in-vitro physiology of a toxic shock syndrome strain of Staphylococcus aureus.

Seven materials used in the manufacture of tampons-four rayon, one modified rayon, one cotton and one carboxy-methyl cellulose (a modified cotton)-were compared for their effects in vitro on the physiology of a strain of Staphylococcus aureus isolated from a patient with Toxic Shock Syndrome. Experiments were performed in broth culture and, with the exception of two rayon samples, all of the materials tested reduced growth rate and cell yield compared with control values. Exocellular acid phosphatase, lipase, proteinase, hyaluronate lyase and haemolysin in culture filtrates were measured and the lethality of filtrates was determined in mice. The tampon materials had different effects on the levels of exocellular products. Cotton and carboxy-methyl cellulose cotton materials reduced the levels of all of the activities tested. The activities of the other enzymes were reduced or increased, depending on which material was present. All materials reduced both haemolytic activity and lethality of the culture filtrates. The in-vitro data suggest an extremely complex interaction between tampon materials and S. aureus.

X-Ray Characterization of Viscose Rayon and the Significance of Crystallinity on Tensile Properties

The paper suggests the analysis of the x-ray diffraction trace of viscose rayon by the correlation- crystallinity index method for routine assessment of crystalline order in samples composed of cellulose II, and by the multipeak-resolution method for special analysis of crystallinity and crystallite size in samples composed of either cellulose II only or cellulose II + cellulose IV. Sets of samples of viscose rayon produced under controlled conditions are x-ray characterized, the tensile properties are measured, and the significance of crystallinity on tensile properties is sought.

Evidence of distinct water species in cellulosic environments from broad‐line NMR

AbstractBroad‐line NMR measurements were made on water in cellulosic samples. The spectra for oriented rayon at 65% relative humidity and room temperature consisted of a visually apparent doublet (SD) and a narrow singlet (SN) which was shifted upfield about 7 ppm from the center of the doublet. The doublet separation varied as A(3 cos2θ—1), where θ is the angle between the fiber axis and the magnetic field; the maximum doublet separation was 350 mG at both 15.1 and 56.4 MHz, indicating the doublet is dipolar in origin. The peak‐to‐peak linewidth of the narrow singlet was orientation and field dependent. The upfield shift of the narrow singlet from the doublet center was field dependent. Spectra for vacuum‐treated rayon consisted of only the narrow singlet, which was orientation dependent. The doublet separation decreases with increasing moisture content and is essentially zero for oriented rayon samples at 100% relative humidity; the resulting spectra due to the collapsed doublet and SN singlet was an asymmetric line. Temperature‐dependent measurements were made on oriented rayon at 65% relative humidity with the fiber axis parallel to the magnetic field; when the temperature was increased from about 0° the peak‐to‐peak linewidth of the doublet halves and the doublet separation decreased. As the temperature was increased from about 30 to about 65°C, a previously unobserved singlet (SE) became visible. The relative amplitudes of the three lines varied with temperature as follows: The SE singlet increased, the SD doublet decreased, and the amplitude of the SN singlet remained constant. Measurements using oriented cotton samples and randomly packed rayon samples indicated that the NMR line shape of the water spectra depends upon the physical properties of the macromolecular substrate. The doublet component of the spectra is attributed to a water species (SD) which is highly bonded to the macromolecular substrate. The SE singlet is attributed to an energetic water species (SE) which is rapidly tumbling in the macromolecular environment. The SN singlet is not due to free water.

A rheological model of viscose rayon

AbstractIn viscose rayon samples subjected to cyclic loading the phenomenon of supertension was observed as a variation of the linear elasticity limit in the consecutive cycles. To enable a mathematical description of this phenomenon a rheological model with an inertional‐frictional element was devised. The curves calculated on the basis of the model well approximated the experimental results.

Trace element distributions in man-made fibers

A preliminary study to evaluate the use of neutron activation analysis for the characterization of six groups of man-made fibers for forensic purposes has been made. A total of 81 samples of acetate, acrylic, modacrylic, nylon, polyester and rayon were analyzed. Small samples, approximately the size typically found during a crime scene search, were analyzed using a Ge(Li) detector system following a 20 min irradiation at a flux of 5·1013 n·cm−2·sec−1. The following elements were determined quantitatively in one or more of the samples: Ti, Sr, Au, Zn, Sb, Br. Mn, Mg, Cu, In, Co, Cu, V, K, Al, Cl, Na, Ca, and S. Significant qualitative and quantitative differences were found both between and within the six groups. However, within certain groups some fibers from different manufacturers showed marked similarities in qualitative and quantitative composition.

Determination of the Viscosity in Cadoxen Solvent of Cellulosic Materials Dyed with Reactive Dyes

A modified cadoxen solvent was used to determine the viscosity of reactive‐dyed cellulosic materials. The conditions for completely dissolving cellulosic materials dyed with different types of reactive dyes were standardised. Reactive‐dyed cotton materials showedno anomalous viscosity behaviour in the cadoxen solvent. With viscose rayon samples dyed with bifunctional reactive dyes, higher viscosity values were observed when measurements were carried out immediately after dissolution. However, on storing the solutions for a further 24 h, the viscosity values became independent of the type or the amount of dye andwere identical with those of undyed rayon. Thus, measurements of the viscosity of reactive‐dyed materials can be conveniently carried out in cadoxen solvent.

Publications Sponsored by the Colour Measurement Committee—III

Two further sets of results, including data from measurements made with several tristimulus colorimeters (Colormaster and Color‐Eye) and visual assessments by a relatively large number of observers, have been obtained for (a) a series of matt paint surfaces and (b) a series of gloss paint surfaces in approximately the same region of colour‐space as the wool and viscose rayon samples discussed previously (l). All samples in any set have been assessed by a ranking method, with reference to a standard, and a statistical approach has been used to provide a quantitative estimate of the visual spacing. The number of colour‐difference equations employed has been increased to include the four equations (1964 CIE; Glasser Cube Root; MacAdam Modified Friele; Munsell Renotation) recommended by the CIE for further study. In all cases an estimate has been made of the degree of correlation between instrumental and visual results for all samples (wool, viscose rayon and matt and gloss paints). The established equations all show poor correlation with the visual results, whereas an equation similar to that reported (l) in Part II of this series, which places much less emphasis on lightness weighting, provides a reasonable fit for all samples. There is little evidence that any significant differences exist in the assessment by colourists of paint and textile surfaces, although the reproducibility of instrumental measurements is much better for the former. The results from a single instrument and, in particular, the Colormaster are at least as reliable as the assessments of a single observer and are more reproducible. These and other relevant points are discussed in some detail.

STUDIES OF GRAFT COPOLYMERIZATION ONTO VISCOSE RAYON

Viscose rayon was graft copolymerized by Co60 γ-ray irradiation, being immersed in the aqueous solution of acrylonitrile.The effects of various factors were examined, such as the time of irradiation, temperature, liquour ratio, denier of rayon, the monomer concentration and pH value of monomer solution. Also, using various kinds of rayon samples, the effect of the degree of swelling of fiber was examined and the percentage of grafting was found to be proportional to this property of fiber in solution system.Microphotograph of the cross-section of grafted rayon (percentage of grafting 53.4y.) showed the uniform distribution of graft polyacrylonitrile. Also, graft polyacrylonitrile being isolated by acid hydrolysis method (cf part I), intrinsic viscosity was measured and found to be nearly equal to that of homo-polymer. Furthermore, the X-ray diffraction pattern of graft rayon was found to be composed of pattern of cellulose II and that of polyacrylonitrile. This fact suggests that graft polyacrylonitrile deposits in amorphous region and is crystallized.The practical properties of grafted rayon were measured. The results showed that tensile strength, elongation and degree of crimping increase and tenacity decreases subject to the percentage of grafting.

X‐ray diffraction and infrared spectra studies on the fine structure of rayon improved by high temperature steaming

AbstractFive samples of rayon containing two high tenacity rayons and three textile rayons of viscose and Bemberg types were heat‐treated with high temperature water or steam (110–210°C.) for a few minutes or seconds, and the change in the fine structure was investigated by means of x‐ray diffraction and small‐angle scattering. An additional study by infared spectra was carried out on cellulose films similarly heat‐treated. The crystallinity increased with increasing temperature and extension of the treating time within the range of less than 10%. Crystallites thicken laterally and grow into those of a higher order. Newly formed crystallites are of cellulose IV. The change is more striking in the high tenacity rayon than in the textile rayons. The remarkable reduction in the degree of swelling is considered to be due partially to such development of crystallinity. No clear conclusion could be drawn as to the contribution of junction points in the amorphous region.

MOISTURE RELATIONS OF CELLULOSE. VII—THE HEAT OF WETTING OF DRY VISCOSE RAYON AND ITS TRANSITION TEMPERATURE

The heat of wetting in water of dry stabilized viscose rayon has been measured al a series of temperaturcs between 1°C and 50°C. Comparison with the results obtained previously with cotton cellulose shows that: The heat of wetting lemperaiure curves of the two varieties of cellulose are similar, each being represented by two straight lines meeting at about 23°C, the line on the lower-temperature side being steeper. The two curves thus indicate the same transition temperature for the rayon and cotton samples used. The evolution of heat takes practically the same time for apparent completion with both rayon and cotton and is markedly slower the lower the temperature, indicating that the kinetics of the swelling process is likely to be similar with regenerated and native cellulose. The reproducibility of heat measurements was poorer with rayon than with cotton, especially at the higher temperatures, indicating the variability of rayon. The ratio of the heats of wetting of dry rayon and dry cotton at various ...

FIBROUS ACETYLATION OF HIGH TENACITY RAYON AND ITS FINE STRUCTURAL CHANGES

All-skin type high tenacity rayon was acetylated in fibrous form in the mixture of acetic anhydride and xylene using CH3COONa as catalyzer. The mechanical properties, namely strength, elongation and especially the elastic recovery behavior of the acetylated samples with various acetyl contents were measured. At 0, 1_??_0.5 degree of acetylation the elastic recovery of acetylated samples increases and above that degree, it decreases. The X-ray patterns of partially acetylated rayon samples did not show any remarkable change from that of the original rayon sample until about 0.4_??_0.5 degree of acetylation, namely, in so far as the acetylation reaction followed the 1st order reaction.

Stress-Strain Relationships in Yarns Subjected to Rapid Impact Loading

Stress-strain curves at rates of straining up to 440,000%/min. have been obtained for a number of textile yarns by a technique involving high-speed photography of the yarn following transverse impact. These curves and others obtained at conventional speeds are presented for samples of acetate, triacetate, cotton, polyester, glass fiber, human hair, vinal, nylon, acrylic, rayon, saran, and silk yarns. Also given are specific breaking energies obtained from the areas under the stress-strain curves and by direct measurements involving longitudinal impact speeds of the order of 50 m./sec. These data show how stress-strain curves depend upon rate of straining and provide ratings for the yarns with respect to ability to survive impact and to resist impact without appreciable deformation.

Factors influencing tensile properties of cellulose fibers

Factors influencing tensile properties of cellulose fibers