Kloeckner-Pentaplast of America Inc., a subsidiary of a West German industrial conglomerate, has opened its first polyvinyl chloride plant in the country in Louisa County, Va. edication of the multimillion-dollar plant, located on 270 acres, 20 miles northeast of Charlottesville, is planned for today. The plant will employ 100 persons at first, and expand to 200 employes and annual sales in excess of $20 million by next year, the company said. A company spokesman would not disclose the cost of the plant.

The plant will manufacture polyvinyl chloride film and sheets used in folding boxes for industrial products, blister packaging, containers, food wrappings, phonograph records, stationery and furniture lamination.

Although polyvinyl chloride has been linked to a form of liver cancer, a company spokesman said that the material is used in the Louisa plant at a stage where cancer problems do not exist.

The company decided to locate in the United States because of increasing ocean freight costs, lack of price stability in raw materials and exploration of new markets, the company said.

It chose Louisa County because of its good rail and raod connections and its central location on the East Coast, a good labor market in the area, and tax advantages in the county and state, the company said.

The Kloeckner conglomerate has sales of about $8 billion and 90,000 employes and is one of the 10 largest industrial firms in West Germany, the company said. It said it is also listed among the Fortune magazine's 100 largest non-American companies.