[img] Text

Download (42kB)


A study was undertaken to investigate “effect of different blends of cotton and polyester fibers on the abrasion resistance, crease recovery, tensile strength and hydrophilic properties of contemporary textile fabrics�. Textiles play a vital role in the present day society. All of us use different types of textile products for various uses throughout our lives. The moment a child is born he is sponged with a soft textile fabric and subsequently wrapped in a textile cloth to protect the sensitive body and skin of the new born from environmental hat, cold and dust. We dress ourselves with a novelty of textile garments according to our taste. We sit on fabric covered chairs and sofas and decorate our rooms with textile products and curtains. We walk on textile mats and sleep on textile bed sheets and underlay. Clothing and household textiles are aesthetically pleasing and vary in colour, design, texture and prices. The fiber properties govern the characteristics of the final fabric. Strong fibers make durable fabrics that can be light in weight. Absorbent fibers are good for skin-contact apparel and for towels and diapers. Fibers, which are self-extinguishing, are good for children sleepwear and protective clothing. To analyze a fabric for predicting performance one usually starts with the determination of its fiber content. The knowledge of the fiber properties helps to anticipate the contribution of its fiber content. The knowledge of the fiber properties helps to anticipate the contribution of the fiber to the performance of a fabric and the garment made from it. Fiber properties are determined by the nature of the external and the internal structure and the chemical composition. Natural fibers are subject to growth irregularities and are, therefore, not uniform in size or development. In natural fibers, fineness is a major factor in determining quality. Cotton, flax wool and silk all are natural fibers. Man-made fiber diamet4er is controlled by the size of the spinneret holes and by stretching during or after spinning. Polyester was first made in 1951. man-made fibers can be made uniform in diameter or can be thick and thin at regular intervals throughout their length. Blend is an intimate mixture of stple fibers of different composition, length, diameter or colour spun together into a yarn. A comparative study of fifteen blends of cotton and synthetic fiber, in varying proportions, available in the local market has been made and presented in this thesis. The purpose of the study was to test and experiment the fifteen types of cotton and polyester blends, (including three samples of 100% polyester, 3 samples 100% cotton, 3samples of 50:50 polyester-cotton blends, 3 samples of 80:20 polyester-cotton blend and 3 samples of 65:35 polyester-cotton blends).the samples were subjected to the evaluation of the following functional characteristics: a)Crease Recovery b)Abrasion Resistance c)Tensile Strength d)Absorbency e)Moisture Regain a) Crease Recovery: The bending elasticity is of the greatest importance in the phenomenon of creasing. Creasing. Creases appear when the material is distorted in such a manner the ability of a fiber or fabric to regain its original shape after it has been wrinkled. b) Abrasion Resistance: It is the ability of a fiber to withstand the rubbing or abrasion it gets in everyday use. Abrasion is just one aspect of wear and may be classified as follows: 1. Flex abrasion: in this case rubbing is accompanied by flexing and bending. 2. Plane or flat abrasion: a flat area of material is abraded in plane or flat abrasion. 3. Edge abrasion: The kind of abrasion which occurs at collars and folds. c) Tensile Strength: It is the property of a fiber defined as the ability to resist stress and is expressed as tensile strength (pounds per square inch) or as tenacity (grams per denier). d) Absorbency: It is the ability of a fiber to take up moisture and is expressed in terms of moisture regain which is the percentage of moisture that a bone-dry fiber will absorb from the air under standard conditions of temperature and humidity. Most fibers are hygroscopic, i.e., they bare able to absorb water vapor from a moist atmosphere and conversely desorb or lose water in a dry atmosphere. Moisture absorbency of a fiber play a major party in deciding about the suitability of a fabric for a particular purpose. e) Absorbency: It is the ability of a fiber to fake up moisture and is expressed in terms of moisture regain which is the percentage of moisture that a bone-dry weight. In the light of theoretical and empirical literature, it is observed that a random sample is preferred for research and experiments. The sampling method used to select a fiver or of fabric for testing depends upon the form and amount of material available. It is important to extract maximum amount of useful information form a minimum amount of material selected for test. The region near the selvedges often possesses slightly different properties as compared to the body of the cloth. Therefore fabric within say 2 inches of the selvedge should not be used because of the extra strains on the yarns at either side of the cloth. Laboratory tests were performed at the central testing laboratory of the Pakistan industrial and technical assistance center, (P.I.A.C), Ministry of industries, Government of Pakistan, Lahore, the institute of Textile Technology, Faisalabad and Clothing and Textile laboratory, college of Home Economics, Lahore. Test-A (The Crease Recover Test): Two testers were used for carrying out this test. I) Shirley crease recovery tester II) Total crease recovery tester i) For the Shirley crease recovery test specimens were cut with a template of 2 inches X1 inches size. Each specimen was carefully creased by folding into half and pressing it by placing between two smooth glass plates. After on minute weight was removed. The specimen was taken out and transferred to the fabric clamp on the instrument and was allowed to recover from the crease. After one minute the recovery angle was noted in degrees. Ten readings were taken in a similar way on each test sample and mean was worked out. ii) for performing test on the total crease recovery tester specimens were cut from the fabric in both warp and weft direction 4 cm X 1 cm size. The specimen was folded and creased by placing it under 500-gram weight. After five minutes the specimen was removed and suspended over a wire. Altogether three minutes were allowed after which the distance between the ends of the inverted ‘V� was measured. Test-B (Abrasion Resistance): The flat abrasion test was carried out on “Universal textile abrasion tester� of Japan origin. Weight /load (11/2 lb) was used to make a hole in the fabric in 2-3 minutes. The number of cycles repaired to make the hole in the fabric was recorded. Test-C (Tensile Strength): Tests were carried out on fabric tensile strength tester, of Japan origin, which works in the principle of constant rate of traverse. The specimen was carefully clamped between the jaws to avoid slippage. These clamps were mounted on the machine. As the clamps moved load was applied on the strip. The amount of load applied on the fabric gradually increased till the specimen broke. At this point the applied load was recorded. Test D (Absorbency): The absorbency test was carried out according to ASTM D583-52T, The American standards for testing textile materials. Water drops concurrently from a height of 68� just on one spot. Time, to collect 10 ml of water, which passed through the fabric, was noted. Then readings were taken and the average time was noted down. Test E (Moisture Regain): Moisture regain of the samples was calculated by the “Oven dry method�. The method employed was to weigh the samples, approximately 1�X1�, in their original condition, followed by drying in oven to a constant weight. Dry weight was noted. A total number of 150 specimens were tested from 15 different samples taking 10 specimens from each sample. It was ensured that selvedges that selvedges, folded and creased areas were not used for cutting test specimens. One of the areas of interest to a textiles expert is that of testing. Over the years textile testing has gained immense importance and diversification. New testing instruments are being developed to meet ever increasing requirements associated with new types of man-made fiver, artificial fiber and regenerated fiber as well as the advent of blends of various fibers. The textile industry is endeavoring to determine which fiber mixture or blend is best suited for a specific consumer demand. The use of more than one fiber in a fabric has the following distinctive advantages. 1. To make the fabric more durable, attractive, and serviceable than if it was made from a single fiber source. 3. To improve the texture, hand-feel and luster. 2. To compensate for the drawback of the oth3er fiber or fabric. 4. To lower the cost, so that people of all socio-economic levels can afford to buy. 5. To meet other diversified demands and handling. The present study will be beneficial for the consumer, as it will highlight the critical the critical properties of these blends. The man in the street is totally ignorant of what he wants and he is an easy prey to unscrupulous manufacturers in terms of both cost and quality. If enough information is available to the consumers, they will then be able to make the purchases knowing well what they really need. This and similar studies will go a long way in furthering the interests of the vast majority of the unaware consumers. The findings of this report will serve as a guide to the industry to have optimum cotton and polyester fiber blends meeting the specific end use requirements based on test results like hygroscopicity, the effect of abrasion, tensile strength and crease recovery. Some of the limitations of the present study were as follows. 1.The study was limited to different blends of cotton and polyester available in the local market. 2.The properties like crease-recovery, abrasion resistance, tensile strength and hydrophilic effects were studied while other tests, which could be of importance, were not considered. 3The differences in serviceability of different fabrics were compared. 4Dyed fabrics were not used in the study. 5 Specimens of the same fabric construction were used. The following are some of the important findings of the present study: 1 Crease Recovery: It has been clearly demonstrated that crease recovery angle increases as polyester content increases as polyester content increases. The crease recovery Warp-Way of 100% polyester was 108o, that of 100% cotton was 115o. 50:50 polyester-cotton was 120o,80:20 polyester-cotton was 124o and 65:35 polyester-cotton was 123o. 2.Abrasion Resistance: Abrasion resistance of polyester as compared to cotton was excellent. Abrasion resistance of 100% polyester, after the no of cycles recorded, was 150 cycles, that of 100% cotton was 95, 50:50 polyester-cotton was 115 and 65:35 polyester-cotton was 106 cycles. These were all the warp way readings. 3 Tensile Strength: As the polyester content increased in the fabric breaking strength also increased. Breaking load was recorded in kg for a strip width of 2.5 cm. warp way direction readings f tensile strength for 100% cotton was 31 kilogram, 50:50 polyester-cotton was 39 kilogram, 80:20 polyester-cotton was 48 kilogram and 65:35 polyester-cotton was 41 kilogram. 4. Absorbency: Absorbency of 100% cotton was excellent s compared to 1010% polyester. Absorbency rate of polyester was 30 minutes (1823 second) while 100% cotton had quick penetration in a split of a second, while 50:50 polyester-cotton had 12 minutes (733 seconds), 80:20 polyester-cotton 23 minutes (1432 seconds) and 65:35 polyester-cotton 18 minutes (1098 seconds) 5 Moisture Regain: Since polyester is a hydrophobic fiber therefore it was observed that as its quantity increased in fabrics their ability to absorb moisture from air decreased. Moisture regain of 100% polyester was 0.35% that of 100% cotton was 7.79%, 50:50 polyester –cotton was 4.27%, 80:20 polyester-cotton was 1.89% and that of 65:35 polyester-cotton was 3.37% Textile fabrics can be made beautiful, durable, comfortable and easy to car for. They can satisfy the needs of all people at all times. Knowing how fabrics are created and used will give a better basis for their selection and understanding of their limitations. From the above findings we conclude that polyester fivers accommodate themselves in blends so that a natural look and texture are maintained with the advantage of easy care. Wrinkle recovery, strength, and abrasion resistance of polyester fivers, are excellent, whereas cotton is excellent whereas polyester is deficient. All fibers have good, fair and poor characteristics. Blending enables the technical to combine fibers in optimum ratios for best end-use performance of the fabric.

Item Type: Thesis (Doctoral)
Uncontrolled Keywords: abrasion, crease recovery, tensile strength, hydrophilic propertiles, hydrophilic properties, cotton, synthetic fibre, polyester fibres, blends, hydrophilic fibres
Subjects: H Social Sciences > HB Economic Theory
Depositing User: Muhammad Khan Khan
Date Deposited: 26 Oct 2016 04:45
Last Modified: 26 Oct 2016 04:45
URI: http://eprints.hec.gov.pk/id/eprint/2738

Actions (login required)

View Item View Item