Materials makers Ingenia Polymers Inc. and Sartomer Co. Inc. each are taking steps to expand their presence in the concentrates market.
In the past 12 months, Houston-based Ingenia has commercialized a new chemical blowing agent and a nonmigratory slip additive aimed at improving concentrate performance, technical manager Sushanta Roy said at Thermoplastic Concentrates 2008, held Feb. 25-27 in Chandler.
A patent is pending on the blowing agent, which Roy describes as a proprietary ``green'' additive for polyethylene that can reduce weight by as much as 20 percent in finished parts.
The material is recyclable and can be used on the same equipment used to process PE, Roy added. It also offers lower life-cycle costs compared with PE or polylactic acid resins.
Ingenia's new slip additive has been used in trials using mono- and three-layer coextruded PE films. In those tests, the additive has reduced the coefficient of friction without migrating to the surface, Roy said. The product is aimed at the laminated film market.
The firm also recently completed tests of its four most common chemical-resistant concentrates. In those tests, tensile bars and chips made from high density PE and using those four products showed ``minimal change'' in weight when immersed in acetic acid, toluene, bleach or hydrochloric acid for periods ranging from one to eight weeks.
At Exton, Pa.-based Sartomer - a unit of French materials firm Total Petrochemicals SA - researchers are looking to expand the commercial presence of Sartomer's styrene maleic anhydride resins in standard thermoplastics. Most existing SMA uses are in coatings, inks and carpet-fiber treatment, according to SMA resins technical manager William Dougherty.
In polypropylene, SMA can be used as a polymeric dispersant in calcium carbonate and talc-filled systems. SMA has been shown to improve tensile and flex modulus in 30 percent glass-filled PP and has improved paint adhesion as well, Dougherty said.
SMA also can improve melt flow and physical properties in nylon 6, where Dougherty said SMA is ``an excellent cross-linker'' and also can decrease melt flow. SMA additionally can be a dispersant aid for clay-filled systems for injection molded and large blow molded parts made of nylon 6.
For ABS materials, SMA can function as a plasticizer with a lubricating effect, and can decrease viscosity when used as a processing aid. In color concentrates, SMA has uses as a dispersant aid for organic, inorganic and metallic pigments or fillers. Dougherty said the material ``can increase color development and provide brilliant color.''
Specialty grades of SMA also can be used as an antimicrobial additive in a variety of plastics.
``We're working on additives to move the performance of lower-cost polymers into high-performance applications,'' Dougherty said.