1. POLY VINYL ALCOHOL
1. PRODUCT CHARACTERISTICS
Poly Vinyl Alcohol (PVA) is one of the few high molecular weight commercial polymers, which is water soluble.
Appearance / Dry solidCommercially available in granular or powder form
Properties / The properties of Polyvinyl alcohol vary according to the molecular weight of the parent poly vinyl acetate and the degree of hydrolysis.
Polyvinyl alcohol are highly resistant to solvents, oils and grease. They form tough, clean films that have high tensile strength and abrasion resistance.
Grades / A wide range of grades are available both in fully hydrolysed form and in various stages of unhydrolysed form.
Poly vinyl alcohol is produced in four general molecular weight ranges.
*Molecular weight of Main Commercial Poly vinyl alcohol grades
Viscosity grade / Nominal / MnLow / 25,000 / 5 to 7
Intermediate / 40,000 / 13 to 16
Medium / 60,000 / 28 to 32
High / 100,000 / 55 to 65
2. PRODUCT APPLICATIONS
PVA is not considered as a thermoplastic because the melt temperature exceeds the degradation temperature for fully hydrolysed grades.
By using plasticizers, the resin's melt processing temperature can be controlled at 185 deg.C with an adequate melt flow with improved heat stability.
High boiling methylol compounds e.g. Pentaerythritol and 1,2,6-Hexanetriol are preferred for high temperature processing.
Thus, the polymer can be processed by casting extrusion, injection and blow moulding. The outstanding properties of Polyvinyl alcohol resins have led to their use as a versatile water soluble polymer in diverse industrial applications.
The outstanding properties of Polyvinyl alcohol make it versatile for its following broad industrial uses.
* As a binder in adhesive formulations
* In textile sizing
* As an emulsion polymerisation aid
Other diverse applications are given below:
* As joint cement for building construction
* Water soluble film for hospital-laundry bags
* Emulsifiers in cosmetics
* Temporary protective film
* Soil binding to prevent erosion
* Intermediate in the production of polyvinyl butyral
* Adhesive interlayer in laminated safety glass
* Polyvinyl alcohol fibre
Adhesives: Polyvinyl alcohol is a first class adhesive for corrugated board, paper and paper board and in general purpose adhesives for bonding paper, textile and porous ceramic surfaces.
Fully hydrolysed grades are used for making quick setting and water resistant adhesives for the backing of postage stamps, cartons etc.
Polyvinyl alcohol is also used as modifier for Polyvinyl acetate emulsion adhesives because it increases the stability of functioning as emulsifiers and protective colloids.
The formulations for PVA based adhesives for general packaging used in India are given below.
Composition / PartsPVA Emulsions / 100
Plasticizer / 10 to 15
Dextrin / 0 to 100
Clay Filler / 0 to 30
Preservative / 0 to 2
Stabilizer / 0 to 2
wetting Agent / 0 to 0.2
Secondary water / 0 to 100
Defoamer / 0 to 2
Deodorent / 0 to 1
Paper and Paper Board Coatings: Polyvinyl alcohol is an exceptionally powerful pigment binder for paper and paper board coatings,. pigmented coatings, in grease proof and other speciality coatings.
Cast Film: Unsupported film cast from aqueous solutions of Polyvinyl alcohol and a plasticiser provides a unique combination of water solubility, gas barrier properties and resistance towards organic solvents.
Polyvinyl alcohol films can be used as container liners in packaging of oils, greases and paints.
The use of this water soluble Polyvinyl alcohol film in the packaging of materials such as dyes, detergents, bleach, fungicides, insecticides and other materials which pose health or safety risks, enable dissolving in water without the removal of the package.
Building products: Polyvinyl alcohol improves the performance of cement materials which are used in roof coatings and cement paint, thin-bed tile mortars, dry wall construction and cement toppings for repairs.
Fibre: Polyvinyl alcohol is also used for textile fibre although it must be chemically treated to get water soluble. Polyvinyl alcohol fibre has good strength characteristics. Mainly fully hydrolysed grades of Polyvinyl alcohol are used for the fibre production.
Polyvinyl alcohol is an efficient textile finishing agent which may be used to modify the hand of textile finishes based on thermosetting resins such as Urea formaldehyde and Melamine formaldehyde resins. It is also used as good textile warp size for filament and spun yarn.
On a world-wide basis, textile warp sizing is one of the largest applications for Polyvinyl alcohol.
Materials Bonding: Polyvinyl alcohol acts a good binder for the solid particles including pigments, ceramics, cement and textile fibres. Polyvinyl alcohol is used as a binder for the stabilisation of soil so as to control erosion. It can also be used as a binder in catalyst pellets, cork compositions and variety of other materials.
Cosmetics: The emulsifying binding and thickening properties of Polyvinyl alcohol make it useful for cosmetic applications. Cold creams, shaving creams, eye make-up and facial masks may be formulated using Polyvinyl alcohol.
Chemical Derivatives: One of the most important uses of Polyvinyl alcohol is as a chemical intermediate in its reaction with aldehydes forming Polyvinyl acetals. Poly vinyl butyral is used in the manufacture of automotive safety glass.
3. IMPORTS Around 6500 tonnes per annum
4. EXPORTS Nil
5. INDIAN MANUFACTURERS
There are two manufacturers in India producing Polyvinyl alcohol
* Vam Organics Chemicals Ltd,New Delhi 2000 tonnes per annum
* Polychem Ltd.,Mumbai 2000 metric tonnes
(Not in operation)
6. DEMAND SUPPLY TRENDS
Demand level 7200 tonnes per annum
Estimated growth rate in demand : 12% per annum
7. MANUFACTURING PROCESS
Poly vinyl alcohol is produced from Vinyl acetate monomer.
8. GLOBAL SCENARIO
Global production of PVA Around 4 lakh tonnes per annum
Global demand pattern for PVA:-
Vinylon / 1.15%Textile fibre / 10.28%
Paper / 13.05%
Films / 10.37%
Adhesive / 18.22%
Others / 16.90%
Global production:-
The global production of PVA is about 4 lakh tonnes per year (excluding China), of which about 1.9 lakh tonnes is produced in Japan, followed by USA, France, Germany, UK, Taiwan and Italy, North Korea, Mexico, China has small batch type plants with undisclosed production data.
9. RECOMMENDATIONS
Poly vinyl alcohol has excellent growth potential in demand and the project respect an ideal import substitution investment opportunity.
Recommended capacity 7500 tonnes per annum
Estimated project cost Rs.30 crores