Recycle-based engineering alloys and new nylons in development.

A new PET/polycarbonate alloy containing up to 80% recycled resin represents the vanguard of engineering thermoplastic developments quietly under way at Allied-Signal Inc., Morristown, N.J. Other engineering thermoplastic research programs at Allied-Signal include new nylons with enhanced heat and chemical resistance, and with high melt strength for blow molding.

William P. Greubel, v.p. and general manager of Engineering Plastics, told PLASTICS TECHNOLOGY in an interview last month that the new PET/PC alloy will be formally introduced later this year as part of the company's Synergy line, under the trade name "Impact."

80% RECYCLED CONTENT

The most intriguing aspect of the alloy is its use of recycled resins as feedstock material. Greubel said recycled PET bottles from municipal waste streams, as well as virgin and recycled PC will be used to produce the Impact alloy, with a total recycled content as high as 80%. The alloy also includes proprietary polymer compatibilizing agents.

The alloy represents an eight-year program at Allied-Signal in developing resins originating from post-consumer waste. Included in this effort is work in resource recovery and feedstock preparation. Allied-Signal has capacity to manufacture over 20 million lb/yr of product from recycled resins, mainly post-consumer PET bottles. Based on product demand, this capacity could more than double in a few years, Greubel said.

Allied-Signal has established a supply network for recycled PET feedstock with selected municipalities. Allied-Signal supplies compactors to townships and purchases baled bottles at regular intervals. Independent converters then recycle the material into flake and pellets. Material also will be sourced from major resin recyclers. In the future, Allied-Signal plans to use post-industrial recycled PC in the alloy, as well.

NEW CAPRON NYLON 6 GRADES FOR LARGE-PART BLOW MOLDING
                              D-8272G          D-8370
Specif. Gravity               1.22             1.09
Flex. Str., psi               24,000           10,400
Flex. Mod., psi               674,000          278,000
Notched Izod, ft-lb/in.       0.8              5.0
HDT, F (264 psi)              383              136

Impact will be offered in grades tailored for injection and blow molding, as well as sheet extrusion and thermoforming. Greubel said Impact will have a "slightly higher price" than competing PC/polyester alloys (such as Dow's Sabre, Miles' Makroblend, or GE Plastics' Xenoy), but will offer competitive advantages in the critical area of maintaining impact and mechanical properties under continuous high-heat exposures up to 350 F. Maintaining a part's mechanical properties under long-term heat aging also is expected to be an advantage for Impact.

Applications in developmental testing include small structural automotive parts, electrical/electronic components, and parts for power tools and appliances. (CIRCLE 18)

DIMENSION 'DISAPPOINTING'

Greubel acknowledged that the company's first product in the Synergy line, known as Dimension, has so far received "slightly disappointing" response from customers. Dimension, a nylon/polyphenylene ether alloy previously designated XB 4000, was introduced in late 1989 (see PT, Feb. '90, p. 82; June '89, p. 25).

"The cost/performance window keeps shrinking for this alloy," he said. "We're refocusing our position with Dimension. It appears to be a longer learning process for us with this product." Greubel did say the alloy had found various applications as an extrusion grade. (CIRCLE 19)

An expanded domestic supply of PPE will help reduce the cost of the material and boost its competitive position in coming years, according to Greubel. Allied-Signal obtains its PPE from an unnamed "Asian source." (Mitsubishi Gas Chemical and Asahi Chemical are the only known Japanese producers of PPE). Last year it was reported that a joint venture between Himont Inc., Wilmington, Del., and Mitsubishi Gas Chemical would produce PPE in North America, with an unidentified resin facility expected to come on line by late 1993 (PT, Oct. '91, p. 79; Sept. '91, p. 25). GE Plastics, Pittsfield, Mass., currently is the only domestic producer of PPE.

Dimension was expected to compete with GE's Noryl GTX, another nylon PPE/alloy, for automotive body-panel applications. However, sluggish automotive sales in recent years, as well as slow penetration in body-panel applications and competition from polyester- and polycarbonate-based alloys, have depressed growth in this market niche.

RESEARCH IN HIGH-HEAT NYLONS

Longer-range research at Allied-Signal is directed toward new high-heat nylons that can withstand long-term exposures in excess of 350 F. M.K.K. Rao, director of research & technology in Engineering Resins, said Allied-Signal will explore alloying possibilities along with new combinations of monomers. The major challenge still unresolved is to obtain low moisture absorption and dimensional stability.

Another key focus of the research is on thermal stability in continuous high-temperature service. "Most new high-end polyamides offer good 'one-time' heat spikes, but do not maintain properties under continuous-use high-temperature exposure," Rao observed. "We feel this can be a competitive advantage for our resin."

NEW EXTRUDABLE NYLON 6

A new extrusion grade of Capron nylon 6, said to show heat and chemical resistance similar to nylon 11 and 12 but at one-third the cost, is now in the final phase of market testing and is expected to be commercialized later this year.

Company executives say the new grade is a proprietary alloy, designed for automotive brake liners, cable jacketing and hydraulic tubing, which must endure exposure to zinc-chloride road salts. (CIRCLE 20)

In addition, Allied-Signal also may unveil a new uv stable/weatherable nylon 66 later this year. (CIRCLE 21)

NEW BLOW MOLDING GRADES

Two new blow molding grades of nylon 6 have been commercialized this year for truck and auto component applications. Allied-Signal executives say the melt strength of the new grades has been enhanced to the point where dropping a 5-ft parison is easily achieved. One of the grades, Capron D-8272G HS BK-102, is 12% glass filled, giving it properties required of resonator housings and air ducting. The second grade, Capron D-8370 HS BK5548, includes a special impact modifier system, making it suitable for structural truck components. Both grades have a crystalline melting point of about 420 F. (CIRCLE 22)