Gas-Assist Injection Molding

Gas-assist injection molding (GAIM), a process that uses an

inert gas to create one or more hollow channels within an injection-molded plastic part,

has been around for well over two decades. Used extensively to make products such as

appliance handles and furniture seat backs and frames, GAIM enables manufacturers to

cost-effectively make large struct  ural parts that cannot be produced by the standard

injection molding process.

Likewise, IXEF® polyarylamide compounds produced by Solvay Advanced

Polymers, L.L.C. have long been considered a reliable choice for applications requiring

high strength and stiffness. Because this material provides an excellent surface finish,

even at high glass loadings, it is particularly appealing for structural-type applications

where cosmetics are important.

Until recently, however, the process and the product had never teamed up—that is

until HYXPlastic Services of Broadview, Ill., a market leader in plastic injection

molding for both the major appliance and office furniture industries, decided to bring

them together.

“The coupling of the GAIM process with IXEF compounds has been very

successful,” said Wayne Moore, engineering manager of HYXPlastic Services. “When

you have a hollow piece with a large cross section, you need a material with a lot of

strength and stiffness, and good dimensional stability. IXEF compounds have that. Plus

they offer the added advantage of a durable high gloss surface finish.” 

“We’re very excited by this new opportunity for IXEF compounds,” said Chris

Scarazzo, market development manager for Solvay Advanced Polymers. “By using gas

Gas-assist injection molding, it is now possible to achieve metal-like part performance at a

fraction of the cost.”

For structural applications with high load-carrying requirements, traditional

materials include die cast aluminum, long and short glass-filled nylons, and bulk molding

compounds. According to Scarazzo, each of these materials have shortcomings: high cost

due to secondary operations for die cast aluminum, poor aesthetics and severe mechanical

property loss due to moisture absorption for glass-filled nylons, and high scrap rates for

bulk molding compounds.

According to Scarazzo, potential applications for the GAIM-IXEF resin duo

include office furniture applications, such as seat backs, seat frames, arm rests, and chair

bases, as well as handles, hinges, and knobs for major appliances, such as refrigerators

and dishwashers. 

About HYXPlastic Services

HYXPlastic Services is the industrial plastics division of Wilbert, Inc., a

holding company established in 1999. HYX Plastic Services is the combination of TPI,

the ninth largest thermoformer in the U.S.; TriEnda, a market leader in the material

handling and packaging industry; and Morton Custom Plastics, a market leader in plastic

injection molding and value-added processing.

Headquartered in Broadview, Ill., HYX Plastic Services has nine plant locations

and approximately 1,500 employees. More information about Wilber Plastic Service’s


SINCERE TECH. produces high-performance polymers that are

used in a wide range of demanding applications in the automotive, aerospace, industrial,

foodservice, medical, and electronics industries worldwide. More information about

Solvay Advanced Polymers products and services can be found on the company’s website


Solvay Advanced Polymers is a member of the Solvay Group, an international

chemical and pharmaceutical group headquartered in Brussels, Belgium. The Solvay

Group, whose companies employ about 30,000 people in 50 countries, recorded

consolidated sales for 2004 of EUR 7.9 billion generated by its three sectors: Chemicals,

Plastics and Pharmaceuticals. Solvay is listed on the Euronext 100 index of top European