Overview of Textile Materials: Properties, Classifications, and Identification

This article explores the diverse world of textile materials, delving into their origins, characteristics, and applications. From natural fibers to synthetic innovations, we will provide a comprehensive understanding of common textile fibers, allowing professionals and enthusiasts alike to better utilize these materials in design and production.

1. Classification of Textile Raw Materials

Textile raw materials can be categorized based on their origin and geometric shape/processing method. Historically, natural fibers were predominant, but the advent of chemical fibers has broadened the scope of textile materials significantly.

1.1. Classification by Fiber Source

Textile materials fall into three main categories: natural fibers, chemical fibers, and mineral fibers, as detailed below:

Fiber Category	Subcategory	Fiber Examples
Natural Fiber	Organic Fiber	Plant: Cotton, flax, ramie, sisal; Animal: Silk, wool, cashmere, camel hair
	Mineral Fiber	Asbestos (rarely used in textiles)
Chemical Fiber	Regenerated Fiber	Viscose, cupro, acetate, soybean fiber
	Synthetic Fiber	Polyester, nylon, acrylic, polypropylene
	Inorganic Fiber	Glass fiber, ceramic fiber, metal fiber (rarely used in textiles)

1.2. Classification by Geometric Shape and Processing Method

Textile fibers can also be distinguished based on their form and how they are processed:

• Filaments: Continuous fibers that are not cut during chemical fiber processing, like monofilament or composite yarns.
• Short Fibers: Cut chemical fibers of various lengths, categorized as cotton, wool, or medium-long fibers based on their length and fineness.
• Textured Yarns: Chemical fiber yarns that have undergone deformation processing to enhance elasticity, such as high and low elastic yarns.
• Heterogeneous Fibers: Fibers with varied cross-sections or hollow structures, designed to modify their properties like feel, elasticity, and luster.

2. Natural Fibers

Natural fibers are derived from plants, animals, and minerals. Organic fibers, which include plant and animal fibers, make up the majority of textiles.

2.1. Natural Silk

Natural silk is a protein-based fiber secreted by silkworms. The most common types of silk used in textiles are:

• Mulberry Silk: Cultivated indoors, known for its high quality and smooth texture.
• Tussah Silk: Wild silk, typically from silkworms in natural environments.
• Castor Silk: A less common type of silk derived from silkworms that feed on castor plants.

Silk fiber consists of silk fibroin (the main body of the fiber) and sericin (a protective outer layer). Sericin is removed during processing to reveal the fine, lustrous silk fibroin. Raw silk refers to fabric made with sericin intact, while cooked silk has sericin removed.

Mulberry Silk Characteristics:

Property	Details
Size	2.5-3.5 denier, length 1200-1500 meters
Specific Gravity	Approximately 1.40 g/cm3
Strength	3-4 g/denier, excellent among textile fibers
Elongation	18-21%
Hygroscopicity	About 11%, high among textile fibers
Color	Primarily white and yellow, with a strong, soft luster

Tussah silk has similar properties but with a coarser size and slightly different strength characteristics.

3. Chemical Fibers

Chemical fibers are made from natural high polymers or synthetic polymer compounds that undergo processes like liquefying, spinning, and post-treatment.

3.1. Regenerated Fibers

Regenerated fibers are produced by chemically treating natural high polymers. Common types include:

• Viscose Fiber: Made from cellulose sources like cotton linters or wood pulp. It’s a widely used recycled fiber, known for its good moisture absorption and drapability.
• Cupro Fiber: Derived from cotton linters, with a uniform round cross-section, providing better dyeing properties and softness compared to viscose fiber.
• Acetate Fiber: A cellulose derivative fiber, valued for its luster, elasticity, and silk-like feel.

Key Properties of Regenerated Fibers:

Fiber	Specific Gravity (g/cm3)	Moisture Regain (%)	Strength (g/denier)	Elastic Recovery
Viscose	1.52	12.5	1.8-2.5	Poor
Cupro	1.50	12-13.5	2.5-3.5	Better
Acetate	1.30	6-7	1.3-1.6	Good

3.2. Synthetic Fibers

Synthetic fibers are produced from low-molecular compounds using chemical methods. Key types include:

• Polyester: Known for its strength, resilience, and wrinkle resistance, but with poor moisture absorption.
• Nylon: Characterized by high strength, elasticity, and abrasion resistance.
• Acrylic: Similar to wool, with good resistance to sunlight and microbial erosion.
• Vinylon: Known for its high moisture absorption but poor elasticity.
• Polypropylene: Lightweight, with good abrasion resistance, but poor heat and light resistance.

Key Properties of Synthetic Fibers:

Fiber	Specific Gravity (g/cm3)	Moisture Regain (%)	Strength (g/denier)	Heat Resistance
Polyester	1.38	0.4	4.5-6.0	Good
Nylon	1.14	4.5	4.8-6.4	Moderate
Acrylic	1.14-1.17	1.2-2.0	4-5	Moderate
Vinylon	1.26-1.3	4.5-5	4-6.5	Poor
Polypropylene	0.946	0	4.5-7.5	Poor

4. Short Fiber Yarns

Short fiber yarns are spun from shorter fibers like cotton, wool, or blended fibers, which have different processing requirements.

4.1. Cotton Fiber

Cotton is a plant-based seed fiber, composed mainly of cellulose.

Cotton Fiber Characteristics:

Property	Details
Shape	Flat, tubular, with a characteristic “waist” cross-section
Length	23-31 mm (domestic), 33-45 mm (long-staple)
Strength	3.5-4.5 g/denier (dry)
Elongation	10-13%
Moisture Regain	7-8%

4.2. Wool Fiber

Wool is an animal-based hair fiber, mainly composed of protein.

Wool Fiber Characteristics:

Property	Details
Shape	Round to oval with scales on the surface
Fineness	7-240 μm
Length	6-12 cm (general), up to 40 cm (coarse wool)
Crimp	Natural waviness, affecting fabric feel and elasticity

5. Fiber Measurement Methods

Fiber measurement methods include fixed-length and fixed-weight systems.

• Fixed-Length System:
  • Denier (D): Weight in grams of 9000 meters of fiber. Used for silk and chemical filaments.
  • Tex: Weight in grams of 1000 meters of yarn.
  • Dtex: Weight in grams of 10,000 meters of yarn.
• Fixed-Weight System:
  • British Count (S): Number of yarns 840 yards long weighing 1 pound. Used for short fibers like cotton and wool.
  • Metric Count (N): Meter multiple of length of 1 gram of yarn.

6. Identification using Combustion Method

The combustion method is a simple way to identify different raw materials based on their burning characteristics:

Fiber	Flame	Smell	Ash
Cotton/Viscose	Yellow/Blue	Burning paper/grass	Gray, easily flies away
Wool/Silk	Slow, smoke	Burnt hair/feather	Small balls, easily crushed
Nylon	Melt, blue	Burnt celery	Light brown hard balls
Polyester	Yellow, smoke	Aromatic	Small brown beads, crushable
Acrylic	White, smoke	Fishy	Small black, brittle balls
Vinylon	Small red, smoke	Special	Small brown beads, crushable
Polypropylene	Bright blue	Spicy	Hard, crushable ash

Conclusion

This overview provides a detailed look at textile materials, covering their classifications, properties, and identification methods. With the ongoing advancements in textile science, we can anticipate more sustainable, high-performance fibers that will continue to enhance our world. Understanding these basic principles allows us to better utilize available materials, design novel textile products, and promote responsible textile practices.