HOUSTON - The PVC industry is confident it can withstand assaults on its markets by new-generation polyolefins and elastomers, according to speakers at Flexpo '96, held June 26-28 in Houston. ``We're not overly concerned about PVC replacement,'' said Robert Brookman, president of Colorite Polymers of Ridgefield, N.J. ``We're focusing on how to replace other polymers and materials, and we have been successful.''
New-generation polyolefin suppliers target many current flexible PVC applications for their materials in packaging, medical, automotive, furnishings and other markets. They claim new polymers such as plastomers will have the right properties to do vinyl's jobs. They tout the absence of plasticizers and low levels of extractable chemicals as big benefits for some markets such as medical.
One medical industry official, however, stressed vinyl will be tough to knock out of medical goods.
``PVC's versatility is second to none among all available materials,'' noted K.Z. Hong, manager of materials technology and engineering for Baxter Healthcare Corp. of Round Lake, Ill.
``We tried hard to replace it. That's when we really began to appreciate it and found out how much we took it for granted.''
Hong said polyolefins do not fit well into many current assembly operations to make medical bags, drug delivery systems, tubing and other goods. Polyolefins fall short is some areas like solvent bonding, impact resistance, and kink resistance needed in tubing. PVC tubing in blood-pumping equipment withstands millions of pump-action cycles, and Hong questioned whether any other material could do the job cost-effectively.
One market researcher said new polyolefins have the potential to replace flexible PVC, but hurdles include converters' commitment to PVC and limited exposure to other resins.
``They have their own culture, like the rubber industry,'' said Balaji Singh, president of Chemi-cal Market Resources Inc. of Houston.
Singh predicted that new polyolefins will have the most replacement potential in packaging film and medical goods in the next five years. Singh expects only 240 million pounds of new polyolefins to be used in North America's flexible PVC markets by the year 2005, when these markets could consume 7.9 billion pounds of PVC compounds. PVC is the second-largest volume thermoplastic in the world after polyethylene.
Exxon's new polyolefins perform better than PVC in tensile strength, tear and chemical resistance, low-temperature properties and recyclability, according to Fred Steininger, director of sales development for Exxpol technology polymers. Virgin metallocene resins and metallocene-based compounds will capture many PVC applications. By the year 2005, 660 million pounds of new-generation polyolefins will replace vinyl film and sheet around the world, he predicted.
``The challenge is to fit new polyolefins into PVC processing systems,'' Steininger said in a panel discussion. ``If we can do it, there will be replacement. But it's difficult to generalize on this.''
New polyolefin suppliers are working on grades that can be slush molded, calendered and processed in other ways in which vinyl has had an advantage. New grades will need to match PVC's productivity rates cost-effectively. Even after compounding steps, PVC is a low-cost material. New polyolefin suppliers say their technology is still in its infancy and future polymers will tackle flexible vinyl in auto, medical, packaging and home furnishing markets.
Rexene Products Co. of Dallas reported that its Rexflex FPO propylene polymer is undergoing clinical trials in Europe for dialysis bags. Sam Paton, Rexene director of research and development, claimed Rexene can control Rexflex's crystallinity to provide a high melting point, low tensile modulus, low density and low hardness.
Brookman said Greenpeace's attacks on PVC are a bigger threat to the industry than competition from metallocene polymers. Al-though Greenpeace may continue attacking PVC, North America's vinyl industry effectively has defended the material in low-key communications focusing on its economic benefits. Polyolefin suppliers said they are not taking advantage of Greenpeace casting a cloud on PVC.
``We are not attacking PVC on environmental issues,'' Steininger said. ``But sometimes when a firm replaces PVC, they make a big deal out of it for marketing purposes.''
``Our business strategy is not environmentally driven,'' said Chris Pappas, global vice president of sales and marketing for DuPont Dow Elastomers LLC. ``The market and producers are not interested in frothing [the issue] up.''
Hong said health and safety concerns have made vinyl the most scrutinized polymer in medical applications, and it passes all tests. PVC is equivalent to other materials in environmental im-pacts, claimed Bruce Dovey, senior manager of flexible PVC compounds for Geon Co. of Avon Lake, Ohio.
Vinyl suppliers said they will not stand still against metallocenes.
``There will be new materials to choose from, and the industry will do its development work,'' Brookman said.
He cited new ultrahigh-molecular-weight PVC resins that have rubberlike properties, cross-linked PVC to replace silicone and EPDM, and PVC alloys and grafts with polyolefins for gas barrier properties and chemical resistance.
PVC producers spend a lot on process improvement, and to-day's resins are markedly different, according to Kevin Boyle, market research manager at Occidental Chemical Corp. of Dallas.
No matter how successfully new polyolefins compete, PVC suppliers predict that demand for their resins will grow.
Developing countries will absorb large amounts of PVC as they develop infrastructure like water and sewage piping, and as their citizens buy more disposable and durable consumer goods.
Asian markets will grow fast, but will rely on big imports of PVC or vinyl chloride monomer from North America and other regions with low electric power costs, Boyle said.