Chapter 15 Acetate and Triacetate Fibers Yiping Qiu 是 Donghua University
Chapter 15 Acetate and Triacetate Fibers Yiping Qiu Donghua University
Introduction Fibers in which forming substance is cellulose acetate where not less than 92%o of hydroxyl groups are acetylated: replacing -OH groups with COCH3 Acetate: 2 of 3-OH groups in each 6-member ring are acetylated: 2.5 Triacetate: Nearly all -OH groups are replaced 2.91~2.96 Major use: lining fabrics for suits, coats, draperies
Introduction • Fibers in which forming substance is cellulose acetate where not less than 92% of hydroxyl groups are acetylated: replacing -OH groups with - COCH3 . • Acetate: 2 of 3 -OH groups in each 6-member ring are acetylated; ~2.5 • Triacetate: Nearly all -OH groups are replaced 2.91~2.96 • Major use: lining fabrics for suits, coats, draperies
Structures Surface: straited CroSs-section: lobed Skin-core structure DP:250-300 Much less H-bond than in rayon
Structures • Surface: straited • Cross-section: lobed • Skin-core structure • DP: 250-300 • Much less H-bond than in rayon
Properties Acetate: hydrophilic, thermoplastic Triacetate: hydrophobic, higher melting and softening temperature, high crystallinity Wrinkle easily in hot water: dry cleaning onl Swells in water, mechanical properties change in water Resist to weak alkali and acids Can be bleached
Properties • Acetate: hydrophilic, thermoplastic • Triacetate: hydrophobic, higher melting and softening temperature, high crystallinity • Wrinkle easily in hot water: dry cleaning only • Swells in water, mechanical properties change in water • Resist to weak alkali and acids • Can be bleached
Properties Soluble in acetone Degrade in UV light Burns. melts. forms black beads with vinegar like odder
Properties • Soluble in acetone • Degrade in UV light • Burns, melts, forms black beads with vinegar like odder
Production Similar to cellulose rayon for the first a few steps Cellulose mixed with acetic acid and acetic anhydride, a sulfuric acid catalyst is added acetylation takes place degradation of the polymer making DP low triacetate is made first when water added, some acetyl groups are removed
Production • Similar to cellulose rayon for the first a few steps • Cellulose mixed with acetic acid and acetic anhydride, a sulfuric acid catalyst is added • acetylation takes place • degradation of the polymer making DP low • triacetate is made first • when water added, some acetyl groups are removed
Grades for test 1 number of students 1111 864208642 □ number 29394959697989100
Grades for test 1 number of students 0 2 4 6 8 10 12 14 16 18 20 0 - 9 10 19 20 29 30 - 39 40 - 49 50 - 59 60 - 69 70 - 79 80 - 89 90 - 100 number
Chapter 16 Nylon Fibers Yiping Qiu Donghua University
Chapter 16 Nylon Fibers Yiping Qiu Donghua University
Introduction Nylon: man-made fibers in which fiber forming substance Is any long-chain synthetic polyamide in which less than 85%o of the amide linkages are attached to 2 aromatic rings Invented in 1938 in Du pont Largest market: carpet fiber 80% of market 14%o industrial and consumer products: tire cord fabrics and ropes 11% apparel
Introduction • Nylon: man-made fibers in which fiber forming substance is any long-chain synthetic polyamide in which less than 85% of the amide linkages are attached to 2 aromatic rings • Invented in 1938 in Du Pont • Largest market: carpet fiber 80% of market • 14% industrial and consumer products: tire cord, fabrics and ropes • 11% apparel
Introduction pes Mostly: Nylon 6 and Nylon 6.6 Small amount: nylon 3, nylon 4, nylon 5 nylon 7, nylon 8, nylon 12, nylon 4,6 nylon 6,10
Introduction • Types: – Mostly: Nylon 6 and Nylon 6,6 – Small amount: nylon 3, nylon 4, nylon 5, nylon 7, nylon 8, nylon 12, nylon 4,6, nylon 6,10