SILICONES: MANUFACTURE AND APPLICATION IN
TEXTILES
2
Hitesh R.Wadher
CONTENTS
1. INTRODUCTION 1
2. CHEMISTRY OF SILICONES AND PROPERTIES 2
3. CLASSIFICATION 4
4. MANUFACTURE OF SILICONES 9
5. ROLE OF SILICONE IN TEXTILES 12
6. APPLICATIONS IN TEXTILES
6.1 SILICONE SOFTNER AND FINISHING AGENTS 14
6.2 SILICONE WATER REPELLENTS 15
6.3 SILICONE FABRIC COATING AGENTS 16
6.4 SILICONE ANTIFOAMING AGENTS 17
6.5 SILICONE GREASE, ADHESIVES AND SEALENTS 18
6.6 SILICONE DYE RELEASING AGENTS IN TRANSFER PRINTING 18
6.7 SILICONE IN GLASS FABRIC FINISHING 19
6.8 SILICONE AS FLAME PROOFING AGENTS 19
6.9 SILICONE AS ANTI-BACTERIAL AGENTS 20
6.10 SILICONE IN WASH-WEAR / DURABLE PRESS FINISHES 20
7. METHOD OF APPLICATION 22
8. PRECAUTIONS DURING APPLICATION 24
9. APPLICATION OF SILICONE BY FOAM FINISHIG TECHNOLOGY 26
10. EVALUATION OF FABRIC SOFTNESS BY KAWABATA INSTRUMENTATION 27
11. SILICONE FINISHES ARE PROCESSING PROBLEM SOLVERS 29
12. RECENT DEVELOPMENTS 30
13. ENVIROMENTAL FATE AND EFFECTS 31
14. CONCLUSION 33
15. RE.FERENCES 34
Silicones: Manufacture and Application in Textiles
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Hitesh R.Wadher
1. INTRODUCTION
Silicones are the synthetic compounds containing the elements silicone and oxygen.
They are abundantly available on earth, is hardly found in elemental form. The silicone
content in earth crust is approximately 26 %.
Silicones are among the most versatile polymers and play an important role in Textile
Industry. Today Textile Industry is largest consumer of silicones in India.
Silicones have been used as fabric finishers for many years because of the unique
handle and durability, which makes it extremely cost effective.
Silicone imparts softening to the fabric and also improves physical properties, such as
wrinkle resistance, abrasion resistance and tear strength. The utility of silicone has also been
diversified for many other purposes like antifoaming, thread lubrication and glass fabric
finishing. Silicones give flameproofing and also wash - n- wear finish to the fabric.
Silicones: Manufacture and Application in Textiles
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Hitesh R.Wadher
2. CHEMISTRY OF SILICONES AND PROPERTIES
Silicones are long chain polymers having silicone - oxygen – silicone back bone.
Apart from two oxygen bonds, the tetravalent silicone atom also has two pendant organic
functional groups. These organic functional determine the specific properties of the
polysiloxanes required for the specific substrate.
CH 3 CH3 CH3
R1 Si O Si O Si R1
CH3 R2 CH3
R1: CH3 or OH
R2: Amino, epoxy, carboxyl etc
The specific properties imparted to the fabric by silicones depend upon the nature of
the organic functional groups that are incorporated in the structure of silicone molecule.
Hence, there is a broad spectrum of silicone products to choose from and some of them are
given below:
1) Dimethyl siloxane
These give the fabric water repellency without affecting its breath ability.
2) Methylhydrogenpolysilxanes
This give better softness and water repellency to the fabric than dimethyl siloxane. An
added advantage is that it needs lower curing temperature than the latter.
3) Amino modified siloxanes
This imparts an enhanced softness and smooth feel to the fabric apart from tear
resistance.
4) Epoxy modified siloxanes
This gives the fabric bounce, softness, water repellency and wrinkle and crease
resistance. The finish is extremely durable and also enhances the colour of the fabric.
Silicones: Manufacture and Application in Textiles
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Hitesh R.Wadher
5) Carboxy modified silicones
Its improves the feel of nylon fabric and can be used along with amino and epoxy
modified silicones.
6) Hydrophilic modified siloxanes
This acts as a wetting agent by reducing the kinetic friction between the fabric-fibres.
7) Mercapto modified silicones and amido modified silicones.
These fluids prevent discolourisation by sunlight and are used in making car polish
cloth and furniture polish napkins respectively
8) Polyether modified silicones
These are used as lubricants for fabrics due to their low coefficient of the friction.
(Ref – 1,4)