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Extreme plastics: new contenders push limits of heat & chemical resistance.


Not so long ago, if you needed the ultimate that a thermoplastic A polymer material that turns to liquid when heated and becomes solid when cooled. There are more than 40 types of thermoplastics, including acrylic, polypropylene, polycarbonate and polyethylene.  could offer in heat or chemical resistance, stiffness, and strength, there was a limited number of choices. They were primarily polyether pol·y·e·ther  
n.
A polymer in which the repeating unit contains two carbon atoms linked by an oxygen atom.
 ether ketone ketone (kē`tōn), any of a class of organic compounds that contain the carbonyl group, C=O, and in which the carbonyl group is bonded only to carbon atoms.  (PEEK), thermoplastic polyimide Pronounced "poly-ih-mid." A type of plastic (a synthetic polymeric resin) originally developed by DuPont that is very durable, easy to machine and can handle very high temperatures. Polyimide is also highly insulative and does not contaminate its surroundings (does not outgas).  (TPI (Tracks Per Inch) The measurement of the density of the storage channels on a disk or tape. Track density on magnetic disks has reached 125,000 tpi (125 Ktpi). See bpi, areal density and magnetic disk. ), potybenzimidazole (PBI PBI protein-bound iodine.

PBI
abbr.
protein-bound iodine


PBI,
n See iodine, protein-bound.


PBI

protein-bound iodine.
), high-temperature sulfones, and polyamide-imide (PAI PAI plasminogen activator inhibitor.
PAI Plasminogen activator inhibitor, see there
). Each was represented by one resin family from one supplier, and they quietly carved out respectable low-volume market niches in specialty automotive, semiconductor, aerospace, electrical/electronics, and other industrial applications.

Today it's a more crowded field with additional resin choices and more suppliers, at least one of which coined the phrase "ultra polymers" to identify the peak of the high-performance polymers segment. The "ultra" category is distinguished from what have long been known as "high-performance" thermoplastics--high-temperature nylons, fluoropolymers, polysulfone, polyethersulfone, liquid-crystal polymers (LCPs), polyetherimide (PEI), and PPS (Packets Per Second) The measurement of activity in a local area network (LAN). In LANs such as Ethernet, Token Ring and FDDI, as well as the Internet, data is broken up and transmitted in packets (frames), each with a source and destination address. . While all of the latter are a cut above standard engineering thermoplastics in price and performance, they have limitations in heat or chemical resistance and disadvantages in processing and brittleness.

The "ultras" have broken out of the "high-performance" category and landed at the top tier of the performance pyramid because of a combination of superior thermal properties (HDT HDT Heat Deflection Temperature (plastics)
HDT High Dose Therapy
HDT Heatpipe Direct Touch (Xigmatek)
HDT Heat Distortion Temperature (plastics)
HDT Henry David Thoreau
 of at least 240 C) and other multiple superlatives in strength, toughness, and chemical resistance. "It's a case where they don't necessarily all have the highest heat resistance, but these materials are the best at more than one thing," says Chris Wilson, business director for Solvay's "ultra polymer" line.

The comfort factor

"Ultra" polymers are still a small market with total demand estimated at between 6.6 million and 8.8 million lb/yr for injection molded and extruded applications. But "ultra" polymers are experiencing 15% annual demand growth, according to according to
prep.
1. As stated or indicated by; on the authority of: according to historians.

2. In keeping with: according to instructions.

3.
 various industry observers. Maturing product portfolios and commoditization Commoditization

1. A situation when illiquid financial contracts are changed or modified in a way that promotes trading and results in a more liquid market.

2. Making a product into a commodity.

Notes:
1.
 of certain products like polycarbonate A category of plastic materials used to make a myriad of products, including CDs and CD-ROMs.  and ABS have prompted engineering thermoplastic suppliers to target "ultra" polymers as a potential high-growth opportunity. These suppliers are eager to move away from "commodity" engineering resins and move up the performance chain where there are fewer competitors, more differentiated products, and higher profit margins. Most of these materials range in price from $20/lb to $100/lb. "From the supply side, there are more proprietary products, intellectual protection, and prospects for higher profitability," says Austin Peppin, senior consultant for market-research firm BRG BRG Bridge
BRG Bearing
BRG Bundesrealgymnasium (German: state secondary school)
BRG Bureau des Ressources Genetiques (France)
BRG Business Relations Group
BRG British Racing Green
BRG Best Regards
 Peppin.

A key reason for heightened market demand for these materials is their increased acceptance by design engineers and processors. After a long incubation period incubation period
n.
1. See latent period.

2. See incubative stage.


Incubation period 
, early design and processing challenges have been overcome. Designers and processors see these materials as providing greater value in use despite their high cost/lb. In electronics, product life cycles are growing ever shorter, and ever tinier parts are requiring higher heat and chemical resistance. In addition, end users are under intense pressure to reduce energy consumption through use of more lightweight parts, particularly in the automotive and aircraft industries.

For processors, the obvious question is how well these ultra polymers run on existing injection and extrusion equipment. To date, materials like PEEK have met the challenge while others like Solvay's Torlon PAI, which requires post-curing, have had more limited appeal.

At the higher processing temperatures required, processing machines have more difficulty in efficiently transferring heat from the barrel heaters to the polymer in the screw and in maintaining melt temperatures required to form the part, says Jack Avery of Avery Consultants, Salt Lake City, a former processing expert for GE Plastics. "The issue for processors is the heating capability of their existing equipment; some may have to upgrade the heater bands, while some who already run high-temperature materials High-temperature materials

A metal or alloy which serves above about 1000°F (540°C). More specifically, the materials which operate at such temperatures consist principally of some stainless steels, superalloys, refractory metals, and certain ceramic
 may not need to make changes," explains Avery.

Solvay's Wilson agrees that processors with no prior experience with high-heat polymers "can't just go out and crank up the heat." Modifications in screw configurations and tooling (venting, draft angles, undercuts) must also be addressed.

New players emerge

Victrex USA Inc., the world's leading supplier of crystalline PEEK resin, has been the dominant player in the "ultra" category, but now is being challenged by new and old competitors, mostly on the amorphous side. "For a long time, Victrex had this market all to itself," says BRG's Peppin,.

For one thing, Victrex now has competition in PEEK from Degussa High Performance Polymers and Solvay Advanced Polymers. In fact, the stopped-up market activity in "ultra" thermoplastics is being led by Solvay, which offers the broadest line of "ultra polymers," some developed internally and some added through acquisitions. Other competitors are Mitsui Chemicals America with a thermoplastic polyimide and, most recently, GE Plastics, which brought out a TP polyimide of its own.

Several "ultra" polymers have been around for a long time, but not until now has there been a focused effort to differentiate them from merely "high-performance" thermoplastics. "It's a new way of delineating a higher level of performance," says Howard Blum, v.p. of consulting firm Noun 1. consulting firm - a firm of experts providing professional advice to an organization for a fee
consulting company

business firm, firm, house - the members of a business organization that owns or operates one or more establishments; "he worked for a
 Kline & Co.

The broadest mix

Solvay claims the broadest line of highly heat--and chemical-resistant thermoplastics. A longtime supplier of high-performance resins like Udel polysulfone and Torlon PAI, Solvay has expanded its reach with new product developments and acquisitions. In 2006, the company bought the PEEK polymer line from India's Gharda Polymers and self-reinforcing polyphenylene (formerly known as Parmax) from start-up company start-up company

A new business.
 Mississippi Polymer Technologies. These materials, along with internally developed grades of enhanced high-temperature sulfone sulfone /sul·fone/ (sul´fon)
1. the radical SO2.

2. a compound containing two hydrocarbon radicals attached to the —SO2— group, especially dapsone and its derivatives, which are potent antibacterials effective
 and PAI, have been branded the SolvaSpire family.

Solvay's strategy is to fill the price/ performance gap between PEEK and high-performance materials like PPS. "Previously, end-users were forced to pay for PEEK because there was no cost-effective material to fit the bill," said Solvay's Wilson. New AvaSpire modified PEEK, a lower-cost version with somewhat lower properties, is finding a fit in medical applications as a cost-effective alternative to standard PEEK. The unfilled AvaSpire 650 series is priced 15% to 25% less than standard PEEK. It is used commercially in two medical and surgical devices. While these materials provide high toughness and heat resistance, the lower price brings a compromise in chemical resistance and strength. The 750 series with 40% glass is used as a replacement for reinforced PEEK in industrial and chemical processing applications.

Solvay is also going head to head with Victrex PEEK, offering a drop-in replacement called KetaSpire. It comes in eight grades, including ones with 30% glass and/or carbon fiber. Keta-Spire is made with basically the same process used to make Victrex PEEK (which Solvay also uses to make its sulfone polymers).

The Gatone PEEK products acquired from Gharda are made using a different chemistry, which results in darker color and differences in processability. Solvay offers Gatone primarily in Asia and will discontinue its own Kadel PEEK products.

Both AvaSpire and KetaSpire can be injection molded or extruded on traditional thermoplastic processing equipment. They are made at a semi-commercial plant in Alpharetta, Ga. A new 1.1-million-lb/yr plant is scheduled to come on stream early next year in India. New friction and wear-resistant grades are being developed for both product lines.

On the amorphous resin side, Solvay will introduce a new line of high-heat sulfones called EpiSpire. With an HDT of 230 C to 265 C, these materials will replace roughly equivalent high-heat sulfones produced by different technologies--Solvay's own Supradel HTS HTS Heights
HTS Harmonized Tariff System
HTS High Throughput Screening (biomolecular assay screening)
HTS High-Throughput Screening (Pharmaceutical Industry)
HTS Harmonized Tariff Schedule
 (introduced in late 2004) and Gharda's Gafone PSS-B. Meanwhile, the Torlon PAI line is being "reinvigorated" with several new upgrades, including new friction and wear products. "Up until now, we've under-exploited the potential of PAI," says Wilson. New enhanced grades reportedly will solve difficulties in molding deep undercuts without internal lubricants.

The former Parmax resin, renamed PrimoSpire, is a novel amorphous resin that has no close cousin. It is described as a "self-reinforcing" polyphenylene (SRP SRP - A data link layer protocol. ) with a rigid-rod molecular structure that gives it exceptional compressive strength Compressive strength is the capacity of a material to withstand axially directed pushing forces. When the limit of compressive strength is reached, materials are crushed. Concrete can be made to have high compressive strength, e.g.  (up to 35,000 psi), one of the highest among thermoplastics. It also offers low moisture absorption, high chemical resistance, inherent flame resistance, and 60% greater strength and stiffness than unreinforced PEEK or PEI. Injection molding injection molding
n.
A manufacturing process for forming objects, as of plastic or metal, by heating the molding material to a fluid state and injecting it into a mold.
, extrusion, and compression molding Compression molding is a method of molding in which the molding material, generally preheated, is first placed in an open, heated mold cavity. The mold is closed with a top force or plug member, pressure is applied to force the material into contact with all mold areas, and heat  grades are available.

PrimoSpire chars instead of burning, providing a protective layer in sensitive electronic shielding. Its flame resistance has won it new aerospace ablative ablative (ăb`lətĭv') [Lat.,=carrying off], in Latin grammar, the case used in a number of circumstances, particularly with certain prepositions and in locating place or time. The term is also used in the grammar of some languages (e.g.  applications. SRP costs around $60/lb, about 20% more than standard PEEK.

New challengers in PEEK

Victrex PEEK was patented by ICI (language) ICI - An extensible, interpretated language by Tim Long with syntax similar to C. ICI adds high-level garbage-collected associative data structures, exception handling, sets, regular expressions, and dynamic arrays.  in 1978 and later spun off into a separate company. Tim Herr, Victrex's North American North American

named after North America.


North American blastomycosis
see North American blastomycosis.

North American cattle tick
see boophilusannulatus.
 market development leader, distinguishes the company from its new competition because it is dedicated to that one polymer. "We're a polyketone company, so we compete on a different level."

Global demand for PEEK has exploded over the last decade. Victrex experienced nearly 19% poundage POUNDAGE, practice. The amount allowed to the sheriff, or other officer, for commissions on, the money made by virtue of an execution. This allowance varies in different states, and to different officers.  growth in 2006 in automotive, industrial, food processing, electrical/electronics, and semiconductor markets. In the six months ending March 31, 2007, Victrex's sales of 2.83 million lb were 15% ahead of the same period a year ago. To meet growing demand, a second plant in the U.K. will boost capacity from 6.16 million to 9.35 million lb/yr when it goes online in October.

In 2001, Victrex founded a separate wholly owned subsidiary Wholly Owned Subsidiary

A subsidiary whose parent company owns 100% of its common stock.

Notes:
In other words, the parent company owns the company outright and there are no minority owners.
, Invibio, to supply biocompatible biocompatible /bio·com·pat·i·ble/ (-kom-pat´i-b'l) being harmonious with life; not having toxic or injurious effects on biological function.  PEEK-Classix medical grades and implantable PEEK-Optima grades. Its first implantable application was a Japanese arthroscopy Arthroscopy Definition

Arthroscopy is the examination of a joint, specifically, the inside structures. The procedure is performed by inserting a specifically designed illuminated device into the joint through a small incision.
 device in 2005. Last fall, Invibio introduced Endolign carbon-fiber reinforced PEEK for implantable load-bearing devices.

Among recent Victrex product developments, the company introduced last year Victrex T-Series blends of PEEK and polybenzimidazole (PBI) from PBI Performance Products. Victrex T-Series was introduced for high-temperature applications requiring hardness and wear resistance, as well as improved creep and heat resistance.

The PEEK/PBI alloys come in unreinforced, glass-filled, and wear-resistant versions. A carbon-fiber grade will be introduced soon. T-Series materials boast continuous-use temperatures up to 300 C, compared with 260 C for unmodified PEEK. In semiconductors, a new commercial use is robotic end effectors for silicon wafer pick-up. Other uses include bearings and thrust washers. New PEEK resins and blends are in development.

New PEEK grades with twice the flowability of previous materials are used to replace LCP (Link Control Protocol) See PPP.

LCP - Link Control Protocol
 and PBT PBT Provider Backbone Transport (networking technology adding determinism to ethernet)
PBT Polybutylene Terephthalate
PBT Profit Before Tax
PBT Paper Based Test (education) 
 in thin-wall connectors exposed to lead-free soldering temperatures. These high-heat connectors are smaller and thinner than previous generations.

At press time in early May, Victrex was planning to introduce its first line of PEEK films and new manufacturing capability later that month (the company declined to disclose details in advance).

Besides Solvay's two PEEK families, another new entry comes from JIDA JIDA Jewelry Industry Distributors Association  Degussa, a joint venture 80% owned by Degussa High Performance Polymers and 20% by Jilin University in Changchun, China. Jilin has worked on PEEK manufacturing and processing technology for more than 15 years, according to Christian Bierhaus, director of strategic projects for Degussa HPP HPP

hyperkalemic periodic paralysis.
. Degussa expanded its technology base with the 2005 acquisition of know-how and patents from Ticona GmbH in Germany related to polyaryl ether ketones Ketones
Poisonous acidic chemicals produced by the body when fat instead of glucose is burned for energy. Breakdown of fat occurs when not enough insulin is present to channel glucose into body cells.

Mentioned in: Diabetic Ketoacidosis, Urinalysis
 (PAEK PAEK Polyaryletherketone ). Vestakeep PEEK is produced in China using chemistry similar to that of Victrex and Solvay and is marketed by Degussa. The undisclosed capacity in China is said to be adequate to meet global supply needs and future growth.

Exploding demand for PEEK is fueled in part by increased focus on energy savings via lightweight parts, according to Degussa's Bierhaus. "Ten years ago there was no need to replace metal in gears. Demand is there now because of the unique high-performance polymers that are available to reduce weight and energy consumption." Ultra polymers like PEEK are also meeting the demand for faster processing speeds in industries like electronics.

Vestakeep PEEK's high heat resistance (HDT of 153 to 240 C), chemical resistance, and mechanical properties are comparable to those of competing PEEK resins. The Vestakeep line includes eight grades for injection molding and extrusion. Four unreinforced resins of low to high viscosity (Vestakeep 1000G, 2000G, 3000G, 4000G) are for gears, medical devices, and extruded products. Reinforced grades contain 30% glass or carbon fiber for rigid, low-war-page housings. A specialty molding grade, 4000 FC30, contains 10% graphite, 10% carbon fiber, and 10% PTFE PTFE

polytetrafluoroethylene.
 for self-lubricating bearings and gears. A special unreinforced extrusion grade (3001 G) is for wire and cable. Development areas for Vestakeep PEEK include blends and multilayer coextrusions.

A smaller player in polyketones is Oxford Performance Materials, in business since 2003. It supplies polyether ketone ketone (PEKK PEKK Polyetherketoneketone ) materials, which are said to be growing at a 35% annual rate. "It's taken a while for the market to evolve," says President Scott DeFelice. "The market is now expanding because performance requirements in many industries have climbed beyond what ordinary engineering thermoplastics could provide."

Oxford purchases the resin and has "modest" compounding capacity. Its OxPekk line includes 10 grades for injection molding and extrusion. They comprise high- and low-viscosity resins, both unfilled and reinforced with glass or carbon fiber. OxPekk boasts a glass-transition temperature (Tg) of 162 C vs. 142 C for PEEK. Its compressive strength (30,000 psi) is also higher than PEEK's. Another key feature is the material's slow crystallization Crystallization

The formation of a solid from a solution, melt, vapor, or a different solid phase. Crystallization from solution is an important industrial operation because of the large number of materials marketed as crystalline particles.
, which reportedly yields reduced stress in molded parts. OxPekk costs 20% more than PEEK.

TPI: Now there are two

Faced with commoditization and shrinking margins within its engineering resin line, GE Plastics has penetrated the ultra category with a new thermoplastic polyimide (TPI). Extem is an amorphous polymer with similar processability but much greater heat resistance than its cousin, Ultem polyetherimide. Tg of Extem is up to 311 C and continuous-use temperature is up to 230 C. It was developed to offer performance properties competitive with other ultra polymers plus improved processability.

Two families and a total of seven resins currently comprise the Extem line, but additional grades are expected this year. Extem UH resins have maximum heat and chemical resistance, including enhanced resistance to chlorinated chlorinated /chlo·ri·nat·ed/ (klor´i-nat?ed) treated or charged with chlorine.

chlorinated

charged with chlorine.


chlorinated acids
some, e.g.
 solvents such as methylene chloride. Higher-flow XH resins have a Tg up to 267 C and can fill thin-wall, complex parts. The materials can be molded and extruded on standard equipment.

GE expects to commercialize applications in semiconductor manufacturing, telecommunications, and electrical/electronics this year. GE is working with its LNP (Local Number Portability) The capability of keeping the same local telephone number when switching carriers. See NP and WLNP.  business unit to develop blends with crystalline resins to gain more flow and chemical resistance. Targeted applications include down-hole oil and gas production equipment, bearings, and gears. New wear-resistant and electrostatic-dissipative versions of Extem and blends with other polymers are being pursued.

A third family, Extem VH, is slated for introduction next year. It will offer up to three times more impact strength with the same flowability and heat resistance as the current materials. GE is currently supplying from a U.S. semi-works plant. A large-scale facility is scheduled for startup in 2008 in Cartagena, Spain.

Extem is the second entry in the TPI category, which was pioneered by Mitsui Chemicals in the early 1990s. Its Aurum TPI provides a continuous-use temperature up to 465 C, tensile strength to 38,000 psi, low outgassing Outgassing (sometimes called "Offgassing," particularly when in reference to indoor air quality) is the slow release of a gas that was trapped, frozen, absorbed or adsorbed in some material. , and chemical resistance. Even higher-heat grades with HDT up to 300 C are in development. Aurum is amorphous in its as-molded or extruded form, but parts become crystalline with subsequent heat treatment--which is necessary to develop the ultimate properties of the material.

According to Mitsui business director Masayuki Makihara, injection molded automotive, industrial, and semiconductor applications include gears, seal rings, bearings, retainers, bushings, thrust washers, burn-in sockets, thermal and electrical insulators, and trays and carriers for semiconductor and hard-disk manufacturing.

Aurum can be extruded into film from 0.75 to 22 mils thick, as well as thin-wall tubing, rods, and wire/cable insulation as thin as 1 mil.

PBI stands alone

Polybenzimidazole (PBI) is a unique amorphous thermoplastic produced by one supplier. It was commercialized by Celanese Corp. in 1983 as a flame-resistant fiber for astronauts' garments. The business was later sold to PBI Performance Products. Celazole PBI is said to have the highest Tg (427 C) and HDT (435 C at 264 psi) of any thermoplastic. It withstands brief exposure up to 760 C and also retains its properties down to -196 C. PBI does not burn and produces little or no smoke or off-gases at 1000 F. It is highly resistant to acids, bases, and chemicals. At 58,000 psi, it boasts the highest compressive strength of any thermoplastic or thermoset A polymer-based liquid or powder that becomes solid when heated, placed under pressure, treated with a chemical or via radiation. The curing process creates a chemical bond that, unlike a thermoplastic, prevents the material from being remelted. See thermoplastic. .

Because it has no standard melting point, Celazole is available as a 100-mesh powder for compression molding. Molding requires high temperature (475 C) and pressure (8000 psi). PBI is also sold as fibers and as a liquid solution for film casting, coating, and impregnation impregnation /im·preg·na·tion/ (im?preg-na´shun)
1. fertilization.

2. saturation (1).


impregnation

1. the act of fertilizing or rendering pregnant.

2. saturation.
. As noted above, Victrex produces injection moldable pellet blends of PBI and PEEK (also sold by PBI as the Celazole T-Series).

Celazole U-60 is a standard grade for bushings and seals in the chemical processing and aerospace industries. High-purity U-60SD grade is for semiconductor applications that are sensitive to trace metals. A carbon-filled, electrostatic dissipative grade, Celazole U-60ESD (1) (Electronic Software Distribution) Distributing new software and upgrades via the network rather than individual installations on each machine. See ESL. , is available from two Japanese suppliers, AZ Electronics in Tokyo, and Splas in Tsu.

NEED TO KNOW MORE?

For more information on these companies and their

products, visit www.ptonline.com/suppliers

Avery Plastics Consulting, Salt Lake City

(801) 583-1328 * www.averyconsultants.com

BRG Peppin, Chesterfield, Mo.

(636) 530-0400 * www.brggroup.com

Degussa High Performance Polymers, Farmington Hills, Mich.

(248) 489-1131 * www.degussa.com

GE Plastics, Pittsfield, Mass.

(413) 448-5700 * www.geplastics.com

Invibio Inc., West Conshohocken, Pa.

(866) 468-4246 * www.invibio.com

Kline & Co. Inc, Little Falls, N.J.

(973) 435-6262 * www.klinegroup.com

Mitsui Chemicals America Inc., Rye Brook, N.Y.

(914) 253-0777 * www.aurumtpi.com

Oxford Performance Materials, Enfield, Conn.

(860) 698-9300 * www.oxfordpm.com

PBI Performance Products Inc., Charlotte, N.C.

(704) 554-3378 * www.celazolepbi.com

Solvay Advanced Polymers, Alpharetta, Ga.

(770) 772-8200 * www.solvayadvancedpolymers.com

Victrex USA Inc., West Conshohocken, Pa.

(484) 342-6001 * www.victrex.com

Learn MORE

Visit Online

www.ptonline.com/articles/200706fa1.html for links to this related article:

* Demand Surge Tightens PEEK Supply, July '01

* New 'Ultra' Thermoplastics Contend for Top of Performance Pyramid, Jan. '07

* Extreme Performance--or Process-ability? New TP Polyimide Offers Both, Jan. '07

Joseph A. Grande, Senior Editor
COPYRIGHT 2007 Gardner Publications, Inc.
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 2007, Gale Group. All rights reserved. Gale Group is a Thomson Corporation Company.

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Author:Grande, Joseph A.
Publication:Plastics Technology
Article Type:Cover story
Date:Jun 1, 2007
Words:2975
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