Tpes Based On New Olefin Block Copolymers Introduced

Pawtucket, RI - A new family of thermoplastic olefin (TPO) elastomers exceeds by a wide margin the performance and softness limitations of conventional TPOs and exhibit processing and physical property advantages over a wide range of other thermoplastics elastomers (TPEs), it was announced recently by Teknor Apex Company.

Tradenamed Telcar OBC, the new TPO compounds are blends of a rigid polyolefin and INFUSE olefin block copolymers (OBC) from Dow, which Teknor Apex uses under a newly established agreement with Dow. Conventional TPOs have rubber phases consisting of EPDM rubber or random ethylene copolymers.

"Olefin block copolymer technology from Dow yields elastomers that bridge previous cost-performance gaps and enable Teknor Apex to provide customers with a true alternative to styrenic block copolymer TPEs" said Suresh Swaminathan, Teknor Apex vice president in charge of the Thermoplastic Elastomer Division. "Telcar OBC TPOs exhibit substantially enhanced physical properties, exceptional processability, and a versatility, in terms of hardness range and fabrication techniques, that is truly remarkable."

According to Dr. Sachin S. Sakhalkar, new business development manager for the Thermoplastic Elastomer Division, Telcar OBC compounds exhibit pronounced advantages in comparison with these standard TPEs:

Conventional TPOs. Telcar OBC compounds provide far more rubberlike elasticity (as measured by compression set at 70 deg. C.), greater tensile strength, tear strength, and elongation, and improved processability, as compared with TPOs with rubber phases of EPDM or random ethylene copolymer. In addition, they will be available in a much broader range of Shore A hardnesses, from the single digits to 90 and above. By comparison, standard TPOs are generally not available below 70.

Widely used styrenic TPEs. In comparison with many grades at equivalent hardness, Telcar OBC compounds exhibit superior compression set, heat aging performance, chemical resistance, and processability, as well as equivalent or greater tear and tensile strength. Another advantage involves aesthetics: "Products made from Telcar OBC compounds have a smooth, silky feel that is ideal for soft-touch grips and surfaces," said Dr. Sakhalkar. "Even with very soft formulations, there is none of the tackiness or tendency to accumulate dust that detracts from cosmetic, personal care, and other consumer items."

In working with Dow, Teknor Apex draws on experience in formulating and compounding many types of TPEs, comprising the broadest range of TPE products available from a custom compounder, noted Dr. Sakhalkar. "Dow's block copolymer technology opens possibilities for entire new families of TPE," he said. "For Teknor Apex, this first new group of OBC-based TPOs is just a beginning."

Potential Range of Telcar OBC Powered by INFUSE Grades and Applications Is Very Extensive

Teknor Apex recommends the new compounds for opaque and translucent applications such as food and beverage packaging, office products, medical devices, consumer goods, and industrial products like hoses, tubes, gaskets, seals, weatherstripping, and wire and cable. Telcar OBC compounds meet FDA requirements for regulated uses.

"Teknor Apex product development specialists have demonstrated that Telcar OBC compounds can be readily extruded into thin sheet and tubing and are so strong and elastic that they can be drawn down to form extremely thin film without tearing," said Dr. Sakhalkar. "Included in our offerings for injection molding are high-flow grades for filling long or intricate parts."

Teknor Apex currently supplies Telcar OBC compounds for injection molding and extrusion. The compounds range from 30 to 75 Shore A in hardness and are available in unfilled and filled formulations, including three unfilled grades that are oil- and plasticizer-free. In development are super-soft, gel-like compounds and formulations for blow molding.

SOURCE: Teknor Apex