Using the Physics of Acoustics to Reduce Weight in Cars


As automotive manufacturers continue to push for improved fuel consumption and lower carbon emissions, they are squeezing every single gram of weight out of every single part that goes into a car.  Meanwhile, however, the pressure to save money and create a smoother, quieter driver experience is also increasing. Greensboro, North Carolina headquartered Precision Fabrics Group, has commercialized a unique nonwoven fabric called Nexus AFR which helps solve the car makers need to improve acoustics and reduce weight without breaking the bank. Physics of acoustics The Precision Fabrics solution is based on the ‘physics of acoustics’ and the science focuses on two dominant properties in part design – thickness and resistance to airflow.  Because sound moves through air in waves of minute pressure variations, the solution has to work for long wavelengths (low frequency) and for short wavelengths (high frequency). The frequency of sound, the wavelength of sound, and the speed of sound are related The thickness of the existing insulation layer is important and determines what low frequency wavelengths can be absorbed.  The new Nexus AFR nonwoven material replaces the traditional black scrim on the surface and controls the mid and high frequency wavelength by managing the sound pressure level variations and ‘trapping’ the energy in the insulation layer of the part.  This makes the composite more efficient than just the Homogeneous insulation material by itself.

Advantages over traditional homogeneous insulation

According to Precision Fabrics’ Richard Bliton, this two material approach has many advantages over the traditional homogeneous insulation, one material approach. “Traditional black scrim – the commodity black scrim used in the auto industry is a descendent of the fabric interlining and lining materials.  The typical nonwoven manufacturing technology is a chembond or thermalbond technology,” explains Bliton. Low cost fibres are carded and oriented primarily in the machine direction and a chemical spray or waterfall coats the web and it is compressed and dried.  The web then has a hot melt adhesive powder sprinkled on the face which is to be reactivated during on processing.  Properties such as FR or repellency can be added to the waterfall treatment. “The strength of this type of web is low compared to other nonwoven structures, but the prime advantage is that it is low cost.   Most of the purchasing specifications for this type of material only specify- fabric basis weight, colour, width, and amount of adhesive.  Acoustic characteristics such as Rayls are not controlled, tested or reported,” Bliton continues. An example, Bliton says, is an automotive hood liner.  A traditional design would have a 30 gsm black nonwoven scrim on the back (B) side, 1600gsm resonated fibreglass about 10mm thick as the insulation layer and a 50 gsm black scrim on the front (A) side. A recently launched next generation hood liner with Nexus AFR was made up of 30 gsm B side, 600 gsm Fiberglass insulation 10mm thick and 100 gsm Nexus AFR on the face.  The weight reduction is 950  grams/m² which is more than 2 lbs/m². In this particular case, the acoustics stayed the same and there was cost reductions generated in the raw material line, and additional improvements in manufacturing related to shorter cycle times required to mould a 600 gsm fibre glass part as compared to a 1600 gsm part. Alpha Cabin Random Incidence Sound Absorption

Automotive industry quick to adopt solution

According to Precision Fabrics Group, the automotive industry is moving quickly to implement this new approach. Parts using the AFR nonwoven are commercial in 10 platforms within 5 OEMs and one major OEM has adopted the low density fibreglass with AFR facing design approach as a worldwide corporate best practice. The focus on reducing weight and cost is one of the drivers for the adoption of the new material, but in some cases a vehicle may have a sound problem that has to be solved.  In these cases, the company says, a properly selected AFR facing can significantly improve that acoustic absorption of the part. The physics based solution offers the acoustic engineer some flexibility to tailor the part to focus the acoustic absorption on mid to high frequency ranges. “Some of the commercial parts on the road are last minute ‘fixes’ to acoustic problems found during pre-launch road tests.   The switch to an AFR facing is an easy change for a part manufacturer and an OEM to make,” Rich Bliton adds. The new fabric meets or exceeds all of the fabric specifications that are in place, the modified part can be made on the same tooling and the improved part will have the same fit as before. “The design approach to build a part with low density material for thickness and an acoustically tuned fabric facing for impedance as opposed to the traditional parts where performance was defined by the weight/thickness of the insulation is a new paradigm.  The science can be applied all types of insulation materials. Each situation will have to be tuned and validated, but early feedback is generating 30-40% weight reductions without loss of acoustic absorption performance,” Bliton concludes.

About Precision Fabrics Group

Precision Fabrics manufactures, markets and sells value-added products and services to selected, highly specified markets. The company’s high-performance products play a key role in several diverse markets, which demand engineered, finished fabrics, the common thread amongst which is  the technical nature of their requirements. Precision Fabrics was the first ISO-qualified textile supplier in the USA. – and ISO continues to provide the discipline and framework for effective and efficient product development, customer service, and manufacturing. Precision Fabrics has been ISO-registered to 9001 since 1993 and upgraded to 9001-2008 in October 2009. Precision Fabrics was created in 1988 via a leveraged buyout from Burlington Industries and continues as a privately-held company today. The company has evolved from a traditional textile company into an engineered materials business, focused on highly technical, high-quality woven and nonwoven fabrics. Today, Precision Fabrics employs approximately 600 people and operates plants in North Carolina, Virginia and Tennessee. Corporate headquarters are located in Greensboro, North Carolina and sales offices are maintained in Greensboro and in Bamberg, Germany. Precision’s Vinton, VA, Plant specializes in weaving some of the most technically challenging continuous-filament fabrics in the world. The Greensboro and Madison facilities are world-class in the range of nonwoven products that they produce.   Ref: http://www.innovationintextiles.com/using-the-physics-of-acoustics-to-reduce-weight-in-cars/

OLEFIN FIBERS


Olefin fibers, also called polyolefin fibers, are defined as manufactured fibers in which the fiber-forming substance is a synthetic  polymer of at least 85 wt% ethylene, propylene, or other olefin units (1). Several olefin polymers are capable of forming fibers, but only polypropylene [9003-07-0] (PP) and, to a much lesser extent, polyethylene [9002-88-4] (PE) are of practical importance. Olefin polymers are hydrophobic and resistant to most solvents. These properties impart resistance to staining but cause the polymers to be essentially undyeable in an unmodified form.

The first commercial application of olefin fibers was for automobile seat covers in the late 1940s. These fibers, made from low density polyethylene (LDPE) by melt extrusion, were not very successful. They lacked dimensional stability, abrasion resistance, resilience, and light stability. The success of olefin fibers began when high density polyethylene (HDPE) was introduced in the late 1950s. Yarns made from this highly crystalline, linear polyethylene have higher tenacity than yarns made from the less crystalline. Markets were developed for HDPE fiber in marine rope where water resistance and buoyancy are important. However, the fibers also possess a low melting point, lack resilience, and have poor light stability. These traits caused the polyethylene fibers to have limited applications.

Isotactic polypropylene, based on the stereospecific polymerization catalysts discovered by Ziegler and Natta,was introduced commercially in the United States in 1957. Commercial polypropylene fibers followed in 1961. The first market of significance, contract carpet, was based on a three-ply, crimper-textured yarn. It competed favorably against wool and rayon–wool blends because of its lighter  weight, longer wear, and lower cost. In the mid-1960s, the discovery of improved light stabilizers led to the development of outdoor carpeting based on polypropylene.

In 1967, woven carpet backing based on a film warp and fine-filament fill was produced. In the early 1970s, a bulked-continuous-filament (BCF) yarn was introduced for woven, texturized upholstery. In the mid-1970s, further improvement in light stabilization of polypropylene led to a staple product for automotive interiors and nonwoven velours for floor and wall carpet tiles. In the early 1980s, polypropylene was introduced as a fine-filament staple for thermal bonded nonwovens.

The growth of polyolefin fibers continues. Advances in olefin polymerization provide a wide range of polymer properties to the fiber producer. Inroads into new markets are being made through improvements in stabilization, and new and improved methods of extrusion and production, including multicomponent extrusion and spunbonded and meltblown nonwovens.

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Olefin Fibers

Production of Poly Ethylene Terephthalate


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PET is a polymer that possesses great importance in the contemporary world of plastics. Being a thermoplastic i.e. recyclable polymer made it the number one choice for numerous applications which satisfies the world need for a greener and more ecological alternative to commonly used plastics such as polyethylene and others.

Nowadays, Two PET grades dominate the global market fiber-grade PET and bottle-grade PET. They differ mainly in the end product properties such as optical appearance and production technologies where these properties can be controlled by molecular weight, intrinsic viscosity, and additives specific to each process or application. Other uses include film production and specialty nylons [17].

The scope of this report will focus on bottle-grade PET because of its high demand especially in the Egyptian market. The report discusses the historical development of PET, its importance, properties and material handling considerations.

Ever since its discovery in the beginning of 20th century several companies were interested n providing production technologies to supply the increasing need for large amounts of PET. Technologies and their current licensors are discussed in detail with their flow sheets, chemistry and specific properties.

The report splits the PET production processes into two main parts; monomer preparation and polymerization. Each of the technologies uses different raw materials, solvents, catalysts and reaction conditions with their advantages and disadvantages. After the detailed market study which has put into account both global and local markets’ considerations, a thorough evaluation study is constructed in the report to evaluate each technology according to standard evaluation techniques displayed in the evaluation section.

The carefully studied numbers and statistics in the market section led us to suggest a suitable capacity for the PET production plant based on many factors listed in the same place. The summation of the work done in this project is shown in the recommendation part where a justified process is selected to produce PET and TPA in Egypt. Further desired information about the report as a whole and any given part is attached to this report in the form of an appendix where much more detailed data can be found.

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PET-Production-Technical-Report

Dyeable Polypropylene Fiber


The ability to dye polypropylene fibers using conventional disperse dyes makes the fibers more attractive for apparel end-uses.

TW Special Report

Polypropylene fibers possess a number of attractive properties when compared to other fibers (See Table 1). Despite desirable properties, polypropylene fibers traditionally have suffered from a major drawback that has limited their adoption in textile apparel applications: In contrast to other fibers, conventional polypropylene fibers cannot be dyed. Instead, the color has to be imparted at the fiber extrusion step through mass coloration or solution dyeing. The process involves adding a relatively thermally stable pigment color during the melt spinning of the fiber. The pigments used are not usually miscible with polypropylene. Thus, the pigments are present as discrete particles in the fiber, and the color imparted becomes permanent in the fiber. While this has the benefit of very good colorfastness, there are two significant disadvantages. The first is that introducing new colors involves a relatively complex color-matching step. The second is the absence of greige goods to be dyed. This means that relatively large lots of fiber are made for every new color, and the time required to go from a new color concept to the final fabric or garment can be long.

There has been a long-standing interest in commercializing a dyeable polypropylene fiber. Ideally, it should have a dyeing profile similar to or compatible with large-volume fibers such as polyester, nylon or cotton, so that it is compatible with the dyeing and related processes that are already well-established. Furthermore, it should not change the essential benefits of polypropylene fibers presented in Table 1, especially its low density and its low surface energy. There have been several attempts to make dyeable polypropylene fibers, but they have not been successful because the resulting product did not meet these criteria.
FiberVisions has developed a revolutionary new polypropylene fiber, CoolVisions™ dyeable polypropylene fiber, that meets the needs of facile dyeing and polypropylene fiber characteristics by incorporating an additive within the polypropylene fiber. The fiber can be dyed using conventional disperse dyes in a manner similar to that used for polyester fibers. The fibers feature a wide array of inherent benefits and properties including:

  • light weight and comfort;
  • cottony softness;
  • easy care, easy wear;
  • moisture management;durability;
  • breathability;
  • thermal insulation; and
  • stain resistance.

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Lightweight And Comfortable

Polypropylene fibers are among the lightest in weight of all commercial fibers. The increased number of polypropylene fibers per kilogram of fabric offers added value compared to many other fibers, resulting in improved coverage for the same weight range or equal coverage in lighter-weight fabrics for comfortable garments. In addition, CoolVisions fibers are inherently softer than traditional polypropylene fibers, resulting in greater comfort, according to FiberVisions. This combination of attributes makes garments made from these new fibers inherently easy care, easy wear.

Moisture Management

According to FiberVisions, CoolVisions polypropylene fibers outperform all other dyeable fibers in low-moisture-absorption tests. In addition, garments made from polypropylene tend to have a high moisture-vapor-transmission rate. This is important in comfort, especially when one wants the skin to stay cool and dry. The mechanical properties of polypropylene fibers are not affected when the fabric is wet an inherent advantage compared to fibers like rayon, which can lose strength substantially.
As with traditional polypropylene, CoolVisions offers excellent chemical resistance and aqueous stain resistance. Bleach and other household cleaning chemicals do not affect the fibers, which also are not attacked by microbial organisms such as mold, mildew and bacteria.

windsurfers
Dyeable polypropylene fibers are suitable for apparel end-uses including sports applications.

Dyeing Characteristics

CoolVisions dyeable polypropylene fibers can be dyed using commonly available polyester high-energy disperse dyes and in standard high-pressure dyeing processes used for polyester fibers, but with lower dyeing temperatures possible. The color range and color-matching process are similar to those for polyester fibers.
The ability to dye fabrics results in many benefits over the use of fabrics made with traditional solution-dyed fibers, including value chain and styling benefits. Some of the value-chain benefits include the ability to store greige goods, match colors quickly, produce smaller lot volumes and serve niche or fashion-related color lines, respond rapidly to market demand, and offer a wider range of colors without greatly increasing inventory costs. There are added financial benefits from reduced working capital needs and shortened production times. Styling benefits include reduction in barré found in solution-dyed garments and the ability to print with dye inks rather than pigment inks. Dye-printed fabrics exhibit a softer hand and better colorfastness than pigment-printed fabrics. CoolVisions fibers also have been engineered to have an inherently soft hand and cotton touch not found in traditional polypropylene fibers.
As noted previously, CoolVisions fibers contain an additive that acts as a dye receptor. The additive is present in the fibers as small domains into which the disperse dyes dissolve during the dyeing process. At dyeing temperatures greater than the boiling point of water, the disperse dyes diffuse readily through the polypropylene fiber into the encapsulated domains of the additive. Under actual garment use conditions — which include much lower temperatures — the diffusion of the disperse dyes back out of the fiber is greatly diminished, resulting in good colorfastness. As with polyester fibers, high-energy disperse dyes should be used to obtain optimum colorfastness.
The approach of encapsulating the additive within the polypropylene fiber has many benefits. The surface of the fiber is essentially unchanged, resulting in excellent aqueous stain resistance and low water absorption. The polypropylene fiber also serves to protect the dyes from chemicals such as chlorine, resulting in excellent bleach fastness.
Since the ability to dye the polypropylene fiber is imparted by the incorporation of an additive, the level of the additive affects the depth of shade. This has a couple of benefits, according to FiberVisions: The additive level can be controlled quite well, resulting in reduced shade sensitivity to processing conditions. In addition, the level can be intentionally changed to produce fibers that dye to different depths, thereby offering an additional styling tool.
FiberVisions officially launched CoolVisions dyeable polypropylene fibers at the recent Outdoor Retailer Show in Salt Lake City. A number of partner companies are currently working with these fibers to develop new fabrics and apparel styles. Activities are underway to develop air-jet spun and filament-type products to broaden the range of styling tools.

September/October 2006

REEF:- TEXTILE WORLD

Moisture Management


  • By:- DR. PETRY, TEXTILE AUXILARIES

  • Definition

In general, „moisture management“ is understood to be the ability of a textile to absorb gaseous or liquid humidity from the skin, to transport it from the inside of a textile to the outer surface and to release it into the surrounding air.

To evalua;te the „moisture management“ of a textile one has to know about both the basic temperature regulation of the human body, and about the properties of the textile required by this regulation.

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Essential Requirements of Fiber Forming Polymers


Both natural and man-made fibres are mainly composed of the compounds belonging to high polymers or macromolecules. Macromolecular structure is necessary for the production of materials of high mechanical strength and high melting point. The natural fibres are found to consist chain molecules of linear molecular type. Further, the chain molecules are oriented into the parallel bundles in the process of growth. Based on these investigations, it is assumed that polymers must satisfy the minimum requirements, if it is to serve as a fibre. These requirements are as mentioned follows:

· Flexibility

The polymer must be linear flexible macromolecule with a high degree of symmetry the effect of cross sectional diameter should be less than 15Å. The polymer should not contain any bulky side groups or chains.

· Molecular Mass

The polymer mass must have a comparatively high molecular mass. The average length of its molecular chain should be in order of 1000 Å or more.

· Configuration

The molecule must have the capacity to adopt an extended an extended configuration and state of mutual alignment.

· Crystallinity

A polymer should have at least a high degree of intermolecular cohesive power. This indicates that the molecular chains should have sufficient number of sites of attraction

· Orientation

A high degree of orientation of the molecules in the polymer is a pre-requisite for producing good tensile strength.

Polymerisation


The term polymerisation defines the process of macromolecules formation through repetition of basic units: it of course applies only to synthesis fibres. In general, polymerisation reactions are activated and controlled during the process by various parameters, as temperature, pressure, catalysers, reaction stabilizers.

The number of repetitive units is termed degree of polymerisation and is a parameter of great significance for fibre properties setting. As the length of the single molecules is not constant, but varies according to a statistical model, the degree of polymerisation or the correspondent molecular weight has to be considered as an average value.

Depending on the various fibre typologies, the degrees of polymerisation may range from some hundred units in the case of polymers obtained through condensation (PA, PES) to some thousand units in the case of polymers resulting from poly-addition (PAN, PP). Under a production and application point of view, the degree of polymerisation is controlled by measuring following parameters:

Relative viscosity ηrel= solution viscosity/solvent viscosity = flow time t1/flow time t2

Intrinsic viscosity ηintr= ηrel /c →0 (concentration vanishing)

Melt flow index MFI = speed rate of the melted polymer at pre-established conditions

Relative viscosity is a parameter which is mostly used to identify nylon, while intrinsic viscosity (obtainable from the relative viscosity also by means of formulas) is used for polyester and the melt flow index for polypropylene. There are basically two mechanisms of chemical reaction available for the synthesis of linear polymers:

Poly-condensation: with this operation two molecules of same type or of different types are joined together to form macromolecules by removing simple secondary products as water, hydrochloric acid, alcohol.

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Fig:- Polycondensation

The prerequisite for reactions of this type is the presence in the molecule (monomer) of two terminal reactive groups with functional properties. The molecules composed of 2,3,4…n monomers are named dimers, trimers, tetramers (oligomers)…polymers.

Some of the mostly used monomers are:

Aliphatic di-acids HOOC-R-COOH (used for nylon 6.6)

Aliphatic di-amines NH2-R-NH2 (used for nylon 6.6)

Aliphatic amino acids H2N-R-COOH (used for nylon 6)

Aromatic di-acids HOOC-Ar-COOH (used for polyester)

Diols (bi-functional alcohols) HO-R-OH (used for polyester)

Thus formed polymeric chains contain, besides carbon atoms, also various atoms (etero-atoms) resulting from the condensation reaction of the functional groups (e.g. nitrogen for polyamides, oxygen for polyester).

b) Poly-addition: this operation joins together several molecules and redistributes the valence links existing in the monomers, however without removing secondary products.

Many unsaturated compounds which are characterized by the presence of a double link between two adjacent carbon atoms as ethylene and its derivatives, polymerise according to this reaction; within this category fall e.g. acrylic and polyolefin fibres.

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FIG: Poly-addition

Among the most used polymers there are ethylene derived molecules with one or more

substitutes of hydrogen atoms.

For example:CH2=CHX

Where X=H,CH3,Cl,CN,OH and other groups.

The chains which are thus formed originate from simple openings of double ethylene links and are therefore characterized by links only among carbon atoms.

Difference between addition and condensation polymerisation processes

Through poly-addition not only secondary substances are removed: reactions follow a chain

process, are quicker, highly exothermic and usually require lower temperatures.

Molecular weights (degree of polymerisation) are higher and it is more likely to have chains

with cross or branched links.

Polymerisation, once it is completed, does not leave behind polymers of intermediate length

(oligomers), but only non-reacted products (monomers).

Poly-condensation, on the contrary, is a process in several stages which leaves behind, among

reaction products, also polymers with low molecular weight (oligomers).

Polymerisation techniques

From a processing point of view, the polymerisation can be carried out by mass treatment, solution or dispersion (suspension, emulsion). From the engineering point of view, the process can be:

• discontinuous, where reagents are entirely pre-loaded into the reactor and, as soon as the polymerisation is completed, the products are completely unloaded. The “batch” technique is used in particular for the production of small lots or of specialty items.

• continuous, where reagents are introduced from one end and reaction products come out from the other (this process is used especially for large productions). The reaction can also take place within a stationary phase (as typical for poly-additions) or at subsequent stages (as in poly-condensations).

Whichever polymerisation method is applied, the reaction products (polymers) can appear as follows:

• in form of a solution to be conveyed to the spinning department;

• in form of a melted polymer to be conveyed directly to the spinning department or to be transformed into grains (chips) for subsequent use ;

• in form of a suspension, from which the polymer is separated and conveyed to the spinning department;

Along with the chemical reactants (monomers and possible catalysts) during the polymerisation stage or anyway in a stage preceding spinning, other additives can be added in order to provide the fibre with certain properties: a product of particular importance is a white dulling agent (titanium dioxide in grains), which is added in small quantities in order to give the fibres a “dull” appearance, which distinguishes them from the untreated fibres which, owing to their brighter and “synthetic” appearance, are named “bright”. Under this point of view, the fibre is termed on the basis of the added quantity of titanium dioxide (dullness degree) as follows:

• bright fibre: a fibre without or with minimal quantities of titanium dioxide;

• semi-bright fibre: a slightly delustred fibre

• semi-dull fibre: usually terms delustred fibres with 0,25-0.5% titanium dioxide contents

• dull fibre: fibre with 0,5-1% titanium dioxide

• superdull fibre: fibre with 1-3% titanium dioxide

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Mohair Fibers


Sources of Mohair.-There are three principal sources of mohair in the world: Turkey, South Africa, and the United States. According to the most reliable information available, there are in Turkey in the region about Angora where the breed of Angora goats originated, approximately 1,200,000 of these goats. In all Africa, but mostly in the Cape Province of the South African Union, there are about 3,585,00o Angoras, with about 5,000,00o goats of the common breeds.

Unfortunately for the preservation of the pure Angora blood, the Turks many years ago began to cross their flocks with the common “Kurd” goats, which resulted in so great an infusion of inferior blood that today all goat raisers agree that there are no pure-blood Angoras left, those now used all being more or less contaminated with the common blood. To conserve its flocks and to preserve to the Turkish people the Angoras in their purest state, the Turkish government some years ago prohibited the exportation of Angoras.

The American Angora raiser has, therefore, but the one source for obtaining new blood to build up the flocks in this country-South Africa; but, fortunately, before the Turkish embargo was passed, some of the best of the Turkish goats had been exported to the United States and also to South Africa, so that in all probability, due to the more intelligent interest taken by the Angora raisers in these countries, it is not likely that much better blood can be procured in Angora itself than can be found in either South Africa or the United States.

Mohair and its uses.-As stated before, in 1910 the American mills used almost 5,000,000 pounds of mohair, about two-thirds of which was of American raising.

Comparing the imported hair with the domestic, manufacturers agree that the domestic lacks brightness and luster and does not spin so well as the Turkish hair. Owing to certain climatic conditions, especially in the Southwest, it is necessary to shear the goats twice a year, which of course results in a much shorter staple, whereas the foreign goats are generally shorn but once a year. Every effort is made to grow as long a staple as possible; in Oregon and in some parts of California, where the goats are sheared but once a year, the production of hair between fifteen and twenty inches in length is not unusual in flocks where the grade has been kept to the highest possible standard. For the United States as a whole, where the fleece is allowed to grow an entire year, the average length is about ten inches.

The following articles are made from mohair: plushes used for railway cars and upholstering furniture, coat linings, dress goods, men’s summer suits, automobile tops, braids, rugs, and carriage robes, imitation furs for women’s and children’s wear, couch and table covers, portieres; false hair from crimped and curved mohair. The skins tanned with the hair on are used extensively for carriage robes, muffs, and trimmings for coats and capes.

The market for mohair is unusually dependent upon the caprices of fashion; let there be a change in fashion’s edict and there may be a great demand for mohair; a remarkable falling off is no less likely to occur at any moment.

Considering the amount of domestic hair now being used by the American mills, it is apparent that the future of Angora goat-raising industry lies in improving rather than increasing the output of mohair. The American people must also be educated to the eating of “Angora mutton.” Most mohair experts agree that when proper care and attention are given, American mohair equals the best South African or Turkish product.

Quality of the hair.-The manufacturers state that the production of domestic hair has improved greatly during the last few years, both in staple and in freedom from kemp or dead hairs. In using the domestic and imported hair the manufacturers usually blend the imported in such a proportion as to enable them to use the mixture in most of their products.

As the goat grows elder, the fiber of the hair becomes straighter and thicker and loses its curly quality as well as its luster; hence the best hair comes from the kids, young wethers, and young does.

The highest grade of mohair should hang in curly ringlets from all parts of the animal’s body. The mohair manufacturers prefer hair not less than six inches in length, one of the most prominent stating that he could use very little of the Southwestern hair on account of its being too short, Some Texas flocks were investigated where the growers had produced fleeces from fifteen to twenty-two inches long; such fleeces were sold for special purposes, bringing very high prices.

The majority of the manufacturers purchase a large percentage of their hair direct from the growers in person, or from selling agencies established by the Angora Goat Association in the West.

The great effort of the Angora raisers of today is to develop a goat that will shear a long, lustrous, curly fleece of fine character and free from the obnoxious “kemp.” Kemp is the long, coarse hair which, with very few exceptions, is found in some quantity on even the best Angoras. It is believed to be a last reminder of the common blood bred into the original herds in Turkey; in the judgment of some of the best growers it will never be completely eradicated. Kemp is objectionable in that it will not take any of the dyes used in dying mohair; for this reason the manufactured goods are defective whenever the kemp is used. Kemp can readily be discovered in a fleece as it lacks the luster or sheen of the true mohair, being a dead, chalky white and coarser than the rest of the fleece.

The average shearing value of the American Angora is not so high as it probably might be, because of the mixture of common blood in many of the flocks. The average goat of higher class flocks shears a trifle over three and one-half pounds, but taking the country over, the average is probably somewhat under two and one-half pounds. A high shearing average is not altogether an evidence of superior mohair. According to the best authority available the average for the Turkish Angora is but two and three-fourths pounds a goat, while that for those of South Africa is above three and one-half pounds each.

Handling goats on range.-In general, the goats are handled much the same as the sheep, save that the constant presence of the herder is not necessary. Many goatherds turn the animals out of the pens in the early morning, sending a dog with them to keep away wild animals. During the day the herder rides out to the herd once or twice to note the direction in which they are feeding. Usually if they are allowed to graze alone, the goats will travel too fast and cover too much country, which is injurious to the range as well as to the animals. Careful herders remain with their goats and check this tendency to travel.

The necessary equipment for raising goats is somewhat similar to that for sheep raising. It is especially necessary that proper sheds should be furnished to shelter the goats during wet weather, as they are very susceptible to moisture.

Contrary to general belief, no domestic animal is more fastidious as to its food than the Angora. When fed hay or other artificial food, every care must be taken to keep the food away from the mud and dirt; Angoras will refuse to touch any food which is soiled or trampled into the ground. Muddy or foul drinking water will not answer, and fresh water must be furnished if these animals are to do well either on the range or in feed lots.

Angoras will always endeavor to find shelter from approaching storm and must have sheds under which to creep during stormy weather. As long as it is clear and cold, or the snow is dry, they are comfortable and remain out; but their long, open fleece is soon soaked in the rain, and is seriously affected by the moisture on their bodies.

Angoras require plenty of air and light, and all sheds provided must be open as much as is compatible with keeping out rain or snow. The pens should never become muddy, for the long, silky fleece will easily pick up a great weight of mud, which not only burdens the animal but stains and injures the fleece as well.

Contrary to the general idea, the raising of Angora goats is rather difficult. The young are more delicate than lambs, and their mortality is greater, especially among the well-bred animals. Incessant personal care is absolutely necessary in raising the kids until they are about two months old. The methods of raising the kids are many, especially during their early weeks, when it is inadvisable to let them follow the doe out upon the ranges.

The browsing habit of the goats renders them available even on land where other domestic animals would not find sufficient feed. Goats relish and thrive on all manner of browses; on leaves, shrubs, and small trees, and on moderate amounts of weeds and grass. Despite the general opinion, goats will not do well on brush alone, although a large part of their food is browse. Because of their liking for browsing, goats are occasionally introduced into many states solely for the purpose of clearing the land of brush and bringing it into pasturage. This same browsing habit has caused their exclusion from many parts of the national forests throughout the West, and from watersheds where it is desirable to protect the brushy cover in order to prevent erosion and the filling up by silt of the reservoirs for water supply.

The land upon which goats thrive best being generally useless for other domestic animals, its actual or rental value is generally much below that of pasture land for sheep or cattle, although on the various national forests practically the same fees are charged for goats as for sheep. The total average yearly cost for grazing for one goat is about the same as that for one sheep in the same region, or sometimes a little less. This statement refers, of course, to rangeraised goats and not to those raised in small flocks upon farms or within small pastures.

Receipts from raising Angora goats.-The average receipts from mohair are approximately $1.02 for each goat. Owing to the varying conditions under which the mutton is sold it is impossible to compute any averages from that source which would be applicable to the entire goat-raising region.

Soy Fibers


Soybean protein fiber is a new type of textile material. It has been praised by industry expert as the Healthy and Comfortable Fiber of 21 Century.

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Properties of this fiber are excellent. It has many merits of natural fiber and chemical fiber: thinness, lightness, high strength (tenacity), good resistance to acid and alkali, excellent moisture-absorption and wet-transference etc.

It can be used to produce knitting fabric or weaving fabric which are suitable for underskirt and garment.

Corn Fibers


English: Corn
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CORN fiber has similar characteristics to polyester staple fiber and has the luster of silk, meanwhile its moisture regain surpass polyester, so the fabric made of it is much comfortable. Although the PLA fiber is not inflammable, it has the character of low flammability and smoke eneration ; its flexibility and curl recovery is very good so the
fabric has good shape retention and anti-crease, it has excellent and touch and drape, good dyeability and it can be dyed with dispersion dyes under normal pressure, and it has the character of excellent anti-to fade in color and unaffected by UV light.

Environmental protection: The Corn fiber is produced by the Poly lactic Acid (PLA) which is fermented from the corn amylum. The fiber comes from natural renewable resources, it is the blended fiber and not made of petro chemicals. It can be recycled into fertilizer and decomposable. It has low CO2 and CO emission from burning. Hence it is an environmental material od the 21st Century.

The advantage of Corn fiber:

  • high melt point,
  • high crystallization degree and good clarity.
  • The fiber also has the high strength which is same as normal poly fiber, so its use is very abroad.
  • The Corn fiber has the characteristics of lustrious silk , has excellent hand touch and brightness and so on.

The disadvantage of Corn fiber:

  • the Corn fiber textiles is too rigid and frail.

Characteristics:
Corn fiber is a kind of yogurt polymer. It is tested that Corn knitted fabric will not stimulate skin, and it is beneficialt and comfortable to wear. Corn fiber has excellent drape, slippery, moisture regain and air permeability, and good heat resistance and unaffected by UV light, and it has full lustre and elasticity.