Yaa Biopolymers Inward Fabric Industry

BIOPOLYMERS IN TEXTILE INDUSTRY*

Dr. Asim Kumar Roy Choudhury,
Principal, KPS Institute of Polytechnic, Belmuri, Dt. Hooghly (W.B.)
Ex-Professor as well as HOD, (Textile), Govt. College of Engg. as well as Textile Technology, Serampore
Address: Ushajit, P.O. Belu-Milki -712223, Dt. Hooghly (W.B.)
E-mail: akrc2008@yahoo.in

* Presented inwards Asian Textile Conference xiv held on 26-30 July, 2017 inwards Hong Kong.



Abstract
The basic raw material for textile manufacturing, textile fibres, are non inherently green. They are biodegradable, but more-biodegradable polymers tin sack live made past times biological means. Biopolymers oftentimes receive got a well-defined structure. In contrast, most synthetic polymers possesses much simpler as well as to a greater extent than random (or stochastic) structure.

Biodegradable polymers receive got move of swell involvement inwards recent years mainly for biomedical applications. Biodegradable polymers suspension downwardly inwards physiological environments past times macromolecular chain scission into smaller fragments, as well as ultimately into unproblematic stable halt products. The utilization of biopolymers, i.e. fibres as well as plastics made from corn, sugar, starch as well as other renewable raw materials, has expanded inwards recent years.

Keywords: Textile fibre, Biopolymer, Bacterial polyester, Polylactic acid (PLA), Chitin as well as chitosan

1. INTRODUCTION
With advances inwards chemistry, technological progress as well as the growth of stuff science, a novel grade of synthetised or manmade materials, called polymers or plastics, has been introduced. Due to their remarkable performances, polymers or plastics are everywhere inwards our globe as well as used inwards everyday life inwards a broad gain of applications such every bit textile, nutrient packaging, automobiles, electronics, edifice materials as well as furniture. In terms of properties, polymers are to a greater extent than oftentimes than non lighter than glass, metals or ceramics, tin sack live stiff or flexible and, opaque or fully transparent. Most of the plastics used worldwide are even then made from petroleum; a non-renewable resource. These petroleum-based polymers are extremely resistant to natural decomposition. Consequently as well as after using they accumulate as well as impairment the environs as well as the ecosystem. The lack of biodegradability, environmental concern as well as the depletion of the oil receive got promoted worldwide query to develop biopolymers, bio-based as well as biodegradable polymers, every bit an option to petroleum-based plastics.

The biopolymers receive got been considered inwards the 1940s as well as Henry Ford used soya plastic to create diverse automobile parts inwards an endeavour to demonstrate his belief that ‘farms are the factories of the future’. Biopolymers are produced past times biological systems (i.e. microorganisms, plants as well as animals), or chemically synthesized from biological starting materials (e.g. sugars, starch, natural fats or oils, etc.).They are to a greater extent than biodegradable than vegetable or brute derived natural fibres. Biopolymers volition occupation organisation human relationship for simply over 1% of polymers past times 2015 (Doug, 2010). However, the expected growth is 3-4 times inwards the coming 7-8 years.

The term “biopolymers” is loosely defined every bit polymeric materials consisting for, at to the lowest degree a pregnant part, out of biological components. Where “biological” way (recently) produced past times living organisms, i.e. non produced from petroleum. Biopolymers tin sack live thermoplastic or thermoset, they tin sack live composites or homogeneous as well as they tin sack live biodegradable or not.

A definition for biopolymers sometimes establish inwards patent literature is based on the amount of “modern carbon” that needs to live nowadays inwards a biopolymer. “Modern carbon” is defined inwards the ASTM D6866 touchstone as well as is well-nigh carbon that contains a specific minimum amount of the C14 isotope. In this way it tin sack live proven that the carbon inwards the stuff is non from fossil source (Bleys, 2015).

Biopolymers receive got been known since the dawn of civilization: leather, cotton, wool, natural security as well as cork are all biopolymers. While these materials are even then pop for specific applications, most polymeric materials inwards utilization today are synthetic as well as based on petroleum-derived resources.

In recent years the query as well as evolution of biopolymers has been gaining pregnant momentum, driven past times “green chemistry” as well as sustainability principles which are increasingly adapted inwards the industry. The increased query as well as evolution of renewable loose energy sources, specifically of bio-fuels similar bio-ethanol which is produced from grains or biomass as well as biodiesel which is produced from industrial plant life oils, also drives the evolution of biopolymers. Biodiesel, for example, is produced past times reacting industrial plant life oils with methanol, resulting inwards obese acid methylesters, which is the actual biodiesel, as well as large amounts of glycerol every bit a by-product. The glycerol tin sack live converted to di-functional compounds, which inwards plough tin sack live used every bit monomers inwards biopolymer production.

While some biopolymers similar polylactic acid (PLA) are already becoming commonplace every bit ‘green’ as well as biodegradable packaging materials, others biopolymers are to a greater extent than esoteric. An illustration is BioSteel™ which are poly peptide fibers produced from milk from goats that had been genetically modified with spider silk genes. The polymers are reportedly upwards to 10 times stronger than steel for the same weight (Bleys, 2015).

2. MERITS AND DEMERITS
Biopolymers tardily entering diverse polymer markets namely textile, plastic etc. Their advantages are sometimes shadowed past times their disadvantages, at least, at the nowadays terra firma of development. Before pick of a biopolymer for a item halt use, both merits as well as demerits are to live carefully considered.

2.1. Advantages of Biopolymers

• They are fully bio-based.
• Much lower “oil (petroleum)” is needed for production
• Lower amount of dark-green occupation solid gases emits during their production. Ingeo® (Polylactic acid or PLA from Nature works) requires 60% less greenhouse gases as well as 50% less non-renewable loose energy than other polymers (Ditty, 2013).

2.2. Disadvantages of Biopolymers

• The contest for biological sources for utilization every bit nutrient as well as fuel
• Additional sorting during recycling to avoid contamination.
• Performance even then inferior to oil based polymers – poorer rut as well as wet resistance.

3. APPLICATION OF BIOPOLYMERS
An increasing tendency for biopolymer production as well as application is existence seen due to environmental awareness inwards the past times years as well as eco-friendliness of biopolymers. In the textile sector biopolymers occupy a relatively depression marketplace percentage due to their insufficient mechanical properties compared to conventional polymers, challenges during polymer processing as well as their higher price. The production of biopolymers (commonly known every bit bioplastics) is continuously increasing as well as recorded every bit 1.5 ane M one thousand tons inwards 2012, which is expected to attain to 6.7 ane M one thousand metric tons inwards 2018 (Endres, 2009).

The utilization of bio-based products has grown at a steady measuring inwards the terminal decade. In 2005, they accounted for 7% of global sales as well as about US$77 billion (£49 billion) inwards value within the chemicals sector. One gauge is that past times 2020 the global marketplace for bio-based products volition grow to US$250 billion (£158 billion) as well as that past times 2030, one-third of chemicals as well as materials volition live produced from biological sources, including bio-polymers as well as bio-plastics.

Various factors influence the production, growth of marketplace as well as utilization of biopolymers worldwide, such every bit the convenience of their production as well as processing methods, properties, cost, biocompatibility as well as their dependence from foodstuff-based raw materials. These factors impact the involvement as well as credence of customers for biopolymer products as well as with that the conclusion of polymer producers to actively innovate biopolymers inwards the market. Figures 1 as well as 2 stand upwards for the worldwide %consumption of diverse biopolymers inwards 2013 as well as consumption (in 1000 tons) of biopolymers inwards diverse applications inwards 2011, respectively (Anonymous, 2015).

Figure 1: Worldwide consumption (%) of diverse biopolymers inwards 2013.

Biopolymers receive got versatile applications. H5N1 few are mentioned below:

• Drug delivery systems (medical field),
• Wound closure as well as healing products (medical field),
• Surgical implant devices (medical field).
• Bio-resorbable scaffolds for tissue engineering.
• Food containers, soil memory sheeting, agriculture film, waste materials bags as well as packaging stuff inwards general.
• Non-woven biopolymers tin sack also live used inwards agriculture, filtration, hygiene as well as protective clothing.

The next biopolymers receive got high potential for diverse applications:

• Starch based polymers (packaging)
• Poly Lactide - PLA
• Polyhydroxyalkanoates (PHA)/ Polyhydroxybutyrate (PHB)
• (co)PA – (castor oil based - PA11)
• Polybutylene succinate (PBS) as well as biopolyester based copolymers
• Polyethylene Furanoate (PEF) - option for PET, made from ii edifice blocks, Furandicarboxylic acid (FDCA) as well as Mono Ethylene Glycol (MEG).

Figure 2: Worldwide consumption (in 1000 tons) of biopolymers inwards unlike applications inwards 2011

Biomaterials made from proteins, polysaccharides, as well as synthetic biopolymers are preferred but lack the mechanical properties as well as stability inwards aqueous environments necessary for medical applications. Cross-linking improves the properties of the biomaterials, but most cross-linkers either drive undesirable changes to the functionality of the biopolymers or number inwards cytotoxicity. Glutaraldehyde, the most widely used cross-linking agent, is hard to guide maintain as well as contradictory views receive got been presented on the cytotoxicity of glutaraldehyde cross-linked materials. Recently, poly(carboxylic acids) that tin sack cross-link inwards both dry out as well as wet weather receive got been shown to render the desired improvements inwards tensile properties, increment inwards stability nether aqueous conditions, as well as also promote prison theatre cellphone attachment as well as proliferation. Green chemicals as well as newer cross-linking approaches are necessary to obtain biopolymeric materials with properties desired for medical applications (Reddy et al., 2015).

A special type of ‘application’ is the bio-composites. These are mostly fibre-reinforced composites. Obviously the well-known as well as pop ‘composite woods products’ similar oriented strand board (OSB) or medium density fibreboard (MDF) are bio-composites. In many cases query into these products is focused on improving the environmental properties of the binder, peculiarly on reducing formaldehyde emissions. For the production of fiber reinforced bio-composites all kinds of natural fibers tin sack live used, similar flax, bamboo, natural wool as well as many others that tin sack live bonded together to cast useful composites.

4. METHODS OF MANUFACTURE
In full general in that location are 3 ways to make biopolymers, which are reflected inwards the patent literature:

• Polymers straight extracted or removed from biomass such every bit some polysaccharides as well as proteins. There may live partial modification of natural bio-based polymers (e.g., starch)

• Polymers produced past times microorganisms (fermentation) or genetically modified bacteria such every bit followed past times polymerization or direct bacterial fermentation processes (e.g., polyhydroxyalkanoates). 

• Polymers produced past times classical chemic synthesis starting from renewable bio-based monomers such every bit polylactic acid (PLA).

The plain of application for a polymer as well as its surgical operation inwards technical textiles are depending on its mechanical properties. Thus some other of import factor, which affects its marketplace value, is tensile strength. Polyethylene furanoate (PEF) is establish to receive got amend mechanical properties alongside the biopolymers. Polylactic acid is seen on 2nd seat inwards terms of tensile strength. PEF is currently used for production of bottles as well as the farther applications are restricted due to express production of PEF. The PLA production has already reached industrial scale as well as shows enormous potential inwards many fields of application. The melt spinning of PLA was performed at Extrusion temperature: 230 °C followed past times Quench past times air: 0.55 m/s, eighteen °C at drawing ratio of 1.95 as well as Speed of 2,500 m/min, to obtain “POY” yarn 165 dtex. The yarn was textured (false-twist) at 205 °C earlier the manufacturing of a PLA T-shirt. The filament extrusion was performed successfully, whereas winding appeared to live challenging. The mechanical properties of the spun PLA yarn were compared with reference polyester yarn. The tenacity of PLA yarn is much lower than PET yarn spell elongation is seen inwards same gain (Anonymous, 2015).

5. CLASSIFICATION OF BIOPOLYMERS
Biopolymers tin sack live broadly classified into 3 groups namely:

• Polynucleotides (RNA as well as DNA), which are long polymers composed of thirteen or to a greater extent than nucleotide monomers;
• Polypeptides, which are brusque polymers of amino acids; as well as
• Polysaccharides, which are oftentimes linear, bonded polymeric carbohydrate. This grouping includes alginates, microbial cellulose ( MC ), Chitin as well as Chitosan,

6. IMPORTANT BIOPOLYMERS
A large number of biopolymers are available naturally or manufactured. However, solely a few of them receive got been used commercially. H5N1 few of import biopolymers are discussed here.

6.1.Soybean Fibre
Soybean fibre is a man-made regenerated poly peptide fibre from soybean poly peptide blended with PVA. It is biodegradable, non-allergic, as well as micro-biocidal. The habiliment made from the soy fibre is less durable but has a soft, elastic handle. Soybean poly peptide is a globular poly peptide as well as it has to undergo denaturation past times alkali/heat/enzyme as well as degradation inwards social club to convert the poly peptide solution into a spinnable dope.

6.2. Poly (Alkylenedicarboxylate) Polyesters (APDS)
Monomers for aliphatic APDs tin sack live stone oil derived (i.e. non renewable) or biomass derived (i.e. renewable), the onetime existence the major route. Both tin sack live prepared to the same grade of purity, but the later is even then costlier.

Common dicarboxylic as well as diol monomers establish inwards APDs are shown inwards Figure 3. They include succinic acid (SA), adipic acid (AA), ethylene glycol (EG) as well as 1,4butanediol (1,4BD). Polybutylene succinate (PBS) is aliphatic polyester with similar properties to those of PET. PBS is produced past times condensation of succinic acid as well as 1,4-butanediol.

Figure 3: Dicarboxylic as well as diol monomers establish inwards APDs

PBS is a semicrystalline polyester with a melting call for higher than that of PLA. Its mechanical as well as thermal properties depend on the crystal construction as well as the grade of crystallinity. The Tg is roughly −32°C, as well as the melting temperature is roughly 115°C. In comparing with PLA, PBS is tougher inwards nature but with a lower rigidity as well as Young's modulus (Babu et al., 2013)

Biosuccinic acid (SA) is produced straight past times fermentation of bioengineered yeast as well as E. coli. Catalytic hydrogenation of biosuccinic acid produces 1,4 butanediol, which tin sack also live produced past times fermentation. Bioethylene glycol is produced from bioethylene, a production of catalytic dehydration of fermentation derived ethanol. Bioadipic acid tin sack live produced past times a number of fermentation based processes.

Application: Aliphatic poly(alkylenedicarboxylates) are used inwards polyurethanes for coatings, adhesives as well as foams; Flexible packaging; Agricultural films; compostable bags; as well as inwards blends as well as composites with other biobased polymers to heighten properties (Gotro, 2013).

6.2. Bio-Polyamide (Nylon)
Castor oil has been a non-food crop source of biopolymers. Polyamide xi from castor oil was patented inwards 1944 past times French scientists as well as from 2004 it is marketed past times Arkema every bit Rilsan for sportwear. Toray as well as Radici are directly marketing some other castor oil-derived polyamide, PA 6-10. Sofia launched a hybrid polyamide fibre, Greenfil past times texturising 70% synthetic PA half dozen as well as 30% biosourced PA 10. H5N1 greenfil sock is 5-10 times stronger, but 2-3 times costlier besides (Sofia, 2012).

Bio-polyamides are also a discipline of industrial research, e.g. past times DuPont with co-polyamides prepared from industrial plant life oils, Invista with polyamide terpolymer as well as Rhodia.

6.3. Bio-polyethylene
Polyethylene (PE) is an of import engineering polymer traditionally produced from fossil resources. Bio-based polyethylene has precisely the same chemical, physical, as well as mechanical properties every bit petrochemical polyethylene. The sequence for biological method is every bit follows:

Fermentation of sugarcane/sugar beet/starch crop → bioethanol → distilled at high temperature over a solid catalyst → ethylene → microbial PE or dark-green PE

Bio-polypropylene is at to the lowest degree partially- made from renewable resources using methanol as well as metathesis chemical scientific discipline (Bleys, 2015).

6.4. Biodegradable Polyurethanes (PURs)
PURs are known for toughness, durability, biocompatibility, as well as biostability. Unlike polyester derivatives, polyether-based PURs are quite resistant to degradation past times microorganisms. Biodegradable PURs employed every bit thermoplastics are basically synthesized using a diisocyanate, a diol, as well as a chain-extension agent. The starting fourth dimension representative illustration avoiding diisocyanate is the reaction betwixt a cyclic carbonate as well as an amine rendering the urethane bond. In particular, the polyaddition reaction betwixt L-lysine as well as a bi-functional five-member cyclic carbonate inwards the presence of a strong base. Some receive got reported the enzymatic synthesis of PERs past times enzymatic polyesterification (Lendlein as well as Sisson, 2011).

6.5. Polylactic acid (PLA)
PLA is known since 1845 but non commercialized until early on 1990. It is the solely melt-processable fibre from annually renewable natural resources such every bit corn starch (in the United States), tapioca products (roots, chips or starch mostly inwards Asia) or refined saccharify cane (in the residuum of world). It is thermoplastic, aliphatic polyester similar to synthetic polyethylene terephthalate (PET). The sequence of manufacture steps is every bit follows:

Corn → starch → unrefined dextrose → fermentation → D- as well as L-lactic acid → monomer production → D-, L- as well as meso-lactides → polymer (PLA) production → polymer modification → fibre, film, plastic, bottle manufacture.

The polymerization reaction is shown inwards Equation 1.

PLA has high strength, skillful drape, wrinkle- as well as UV light- resistance properties. Its melting call for is ±170 °C as well as density is 1.25 g/cm³. The limiting oxygen index is 25 higher than PET as well as much higher PP. PLA, therefore, possess reduced flammability, less open fire retardants. Water uptake is depression (0.4 -0.6%) higher than PET as well as PP. It possesses skillful durability nether a gain of conditions.

Not surprisingly a lot of query is even then done on the most mutual biopolymer i.e. polylactic acid (PLA). The query is oftentimes focused on improving polymer properties similar increasing toughness, crystallinity, impact modification etc. Companies similar Metabolix, PURAC, Arkema, Biovation as well as others are active inwards this plain (Bleys, 2015).

PLA is regarded every bit the most promising bioplastic. As a result, it has raised item attending every bit a potential replacement for stone oil based polymers inwards many areas such every bit textiles, bottles, thermoformed containers, newspaper as well as cardboard coating. PLA has a depression rut resistance unless it tin sack live fully crystallised. However, PLA suffers from depression crystallisation kinetics unless it is subjected to high orientations. Hence, increasing the crystallisation charge per unit of measurement inwards processing techniques, such every bit injection moulding, where orientation levels are relatively low, is required to improve its thermal resistance. One way to improve the crystallisation kinetic is to establish out a suitable bioadditives. However, agreement of nucleation as well as crystallisation mechanisms is required to optimise the crystallisation kinetics as well as later on to seat or develop the best bio-based additives.

Figure 4: Chemical construction of PH3B as well as its copolymer PHBV

Application: woven shirts (ironability), microwavable trays, hot-fill applications as well as fifty-fifty engineering plastics. Biomedical applications include every bit sutures, stents, dialysis media as well as drug delivery devices. PLA tin sack live used for stiff thermoforms, films, labels, as well as bottles, but non for hot-fill containers or gaseous drinks such every bit beer or sodas.

6.6. Bacterial Polyesters
One of the most of import fields of query are the polyhydroxyalkanoates (PHA) which are biopolymers produced biochemically past times genetically modified microorganisms or modified plants. The resulting polymers are oftentimes copolymers from 3- as well as 4- hydroxybutyric acid and/or hydroxyvaleric acid. Companies similar Metabolix, as well as Novomer filed patents on this topic. Using the right bacteria PHAs tin sack live produced from wastewater every bit shown inwards a number of patent applications or from waste materials fish- or palm oil or from biogas (e.g. from a landfill digesters). PHA tin sack also live produced from glycerol, algae or fifty-fifty aromatic sources. Poly(3-hydroxybutyrate) or PHB tin sack also live produced from transgenic plants. Examples of a industrial plant life that tin sack live genetically engineered to make PHB are grasses similar switch grass. These grasses are also studied for the bioethanol production inwards the US.

The bacterial polyesters, polyhydroxyalkanoates (PHAs) with poly-(R)-3-hydroxybutyrate (P3HB) every bit the starting fourth dimension homologue (Figure 4), produced past times microorganisms. Bacterial storage chemical compound polyhydroxybutyrate copolymer (PHBV) named “Biopol” is developed past times Zeneca Bioproducts through fermentation of PH3B followed past times copolymerisation with PHV. It is high molecular weight polyester as well as thermoplastic (melts at 1800C) as well as tin sack live melt spun into biocompatible as well as biodegradable fibres suitable for surgical use.

Advantages include production from fully renewable resources, fast as well as consummate biodegradability as well as fantabulous strength as well as stiffness. The disadvantages are high thermal degradability, brittleness as well as high cost (Chod´ak, 2009).

6.7. Sodium alginate fibre
Sodium alginate is a polymeric acid, composed of ii monomer units

(a) L-guluronic acid ( G) (b) D- mannuronic acid (M) (Figure 5)

Figure 5: Two monomers of alginic acid (a) L-guluronic acid (b) D-mannuronic acid

It is non toxic as well as non irritant. Alginate fibre generates a moist healing environs as well as is used for injure dressing. Calcium alginate is created past times adding aqueous calcium chloride to aqueous sodium alginate.

6.8. Chitin as well as chitosan
Both polysaccharides may live regarded every bit derivatives of cellulose, where chitin bears an acetamido grouping as well as chitosan bears a amino grouping instead of the C-2 hydroxyl grouping inwards cellulose (Figure 6).

Chitosan is obtained past times deacetylation of chitin. Chitosan is a linear polyamine having reactive amino as well as hydroxyl groups. It chelates many transitional metallic ions. Currently, the commercial source of chitin is shrimp shells. But the polymer also occurs inwards the shells of crabs as well as lobsters.

Derivatives of chitin receive got been used to impart antistatic as well as soil-repellent finishing to the textiles. While chitin is used inwards printing as well as finishing preparations, spell chitosan is able to take dyes from discharge water. Both receive got remarkable contribution to medical related textile sutures, threads as well as fibres.

Figure 6: The chemic construction of Cellulose, Chitin as well as Chitosan

Chitosan, a Million Dollar Natural Polymer, was discovered past times Rouget inwards 1859, is a technologically of import polysaccharide biopolymer. Chemically it is composed of glucosamine as well as N-acetylglucosamine units linked past times 1−4 glucosidic bonds. Being nontoxic, biodegradable, biocompatible, as well as microbe resistant has given it huge potential inwards a broad gain of scientific areas such every bit biomedical, food, agricultural, cosmetics, textiles, pharmaceutical, as well as other industries (Raafat et al., 2009).

For shrink resistant finishing enzyme treated woollen stuff was finished with 3 unlike finishing polymers as well as the surgical operation properties of chitosan finished woollen stuff are establish to live amend than inwards other finished fabrics. Thermal properties of chitosan finished wool are similar to synthetic polymer finish. Chitosan complete resists the denaturation of wool fibre amend than that of other synthetic finishes. Surface morphology of wool fibre shows that masking of cuticle scales past times chitosan complete is amend than that of other synthetic finishes. Cross-sectional persuasion study infers that chitosan tin sack also live diffused good within the wool fibre. It is concluded that chitosan based shrink resistant finishing could live preferred over synthetic polymer complete for woollen materials (Lakshmanan et al., 2015).

Increased sustainability, environs friendliness, reduced pollution, dark-green chemistry, renewability as well as intrinsic biological activity are some of the attributes which brand chitosan, cyclodextrin, sericin protein, as well as alginate suitable option agents for the functional finishing of textile materials (Islam, 2013).

Recent bio-polymer related patent literature covers a lot of unlike types of bio-monomers which tin sack live turned into polymers using classical chemic synthesis. For example, quite some query is live done on bio-based “polymer grade” acrylic acid as well as methacrylic acid (US patents, US20140206831, US20130165690) which tin sack live produced from bio-derived glycols as well as polyols similar glycerol as well as sorbitol.

7. CONCLUSIONS
Biopolymers are rattling of import inwards all aspects of medicine, surgery as well as healthcare as well as extend of application on which the materials used because of the versatility of biopolymer. Oil is the fuel that drives the global economy, but oil reserves are going down. And in that location are major concerns well-nigh the hereafter because of our swell dependency on oil as well as its impact on the environment.

The global tendency towards sustainability, dark-green chemical scientific discipline as well as renewable loose energy as well as raw materials also has a large impact on the query as well as evolution of polymers. H5N1 large number of patent applications relating to bio-polymers are existence filed, roofing an impressive amount of novel polymers as well as monomers. While real-life applications seem to live express still, this query tin sack live the reason for a strong growth inwards the close hereafter (Bleys, 2015) .

REFERENCES:

1. Anonymous, Melt spinning of bio-based polymers: Overview on properties as well as potential of melt spinnable biopolymers, Melliand International, 2015, 245-6
2. Ramesh P. Babu, Kevin O'Connor as well as Ramakrishna Seeram, Current progress on bio-based polymers as well as their hereafter trends Progress inwards Biomaterials, book 2, number 8, 2013 Green Chemistry as well as Its Application inwards Textile Industry
3. Basic Concepts of Colour Measurement 

 

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