Published : Jun 01, 2013
Polyvinyl alcohols (PVOH) are a group of products that have a similar empirical formula but different properties and applications depending upon their molecular weight and the degree of removal of the acetate groups from the polyvinyl acetate raw material. Fully hydrolyzed grades of PVOH have about 98–99% of their acetate groups hydrolyzed, intermediate grades about 97% and partially hydrolyzed grades about 88%.
PVOH is used neat as a textile warp size, as an adhesive and an additive to adhesives, in paper manufacture primarily as a binder and as a polymerization aid. PVOH is used as an intermediate in the manufacture of polyvinyl butyral (PVB) resin, although it is not required that the PVOH be fully refined during the processing from vinyl acetate monomer to polyvinyl butyral.
The following pie chart shows world consumption of polyvinyl alcohols:
China, Japan and the United States continue to be the world's largest producers and consumers of PVOH. The high production levels in Japan and in the United States are supported by large exports. China produces and consumes more than half of world consumption. The polyvinyl alcohol market is at continued high risk for consolidation of producers as new plant capacity has been added in China.
In China, besides use as a polymerization aid, the major markets for PVOH are for textile sizing agents, architectural applications, fibers, paper coatings and adhesives. Demand is forecast to grow at an average annual rate of 5.8% from 2012 to 2017.
In the United States, most of the applications for polyvinyl alcohol are mature. The fastest-growing market for PVOH is in the manufacture of polyvinyl butyral; growth for this application is forecast at 4.5% annually during 2012–2017. Overall demand growth for PVOH in the United States is projected to be 2.3% per year from 2012 to 2017.
In Western Europe, demand growth for PVOH will depend primarily on demand for polyvinyl butyral resin, which is one of the largest and fastest-growing markets for PVOH in the region. The other traditional markets are expected to recover and increase, and new applications such as ceramic binders and water-soluble and biodegradable thermoplastic polymers could result in higher growth rates than forecast. Demand is forecast to grow at an average annual rate of 3.6% from 2012 to 2017.
In Japan, total consumption of PVOH is expected to recover and increase after the global economic recession at about 3.5% annually from 2012 to 2017. Most PVOH applications will increase for the next five years.