Structural Foam Molding is a low-pressure foam injection molding process where molten resin is injected with nitrogen gas or a chemical blowing agent. The resin is then shot into the cavity, without overfilling or packing it out. The blowing agent or gas then expands to push the molten resin to the extremities of the cavities. As the part cools, the internal pressure of the foaming action takes up the internal shrinkage and reduces sinks over ribs or heavy cross-sections.

Transparent in its natural state, the variety of acrylic polymer grades available for use during the injection acrylic molding processes can achieve most any finish that your product requires. Specialized additives inserted during the injection process allow acrylic to become heat resistant and more impact resistant. In addition, acrylic plastic price falls at the midpoint of the pricing spectrum for injection materials and offers:

A Lomont product that is molded using the structural foam process will typically have a surface which appears to have swirls on it.  This is due to the internal “foaming action”, in which some of the small internal bubbles come to the surface of the part. A cross-section of a structural foam molded part will show a cellular internal core sandwiched between two solid wall sections.

PMMA lens are widely used in a multitude of industries and applications when light transmittance, as opposed to diffusion, is a performance mandate. The properties of the material make it popular for:

Acrylic plastic represents a family of petroleum-based thermoplastics made from the derivation of natural gas. Sometimes referred to as "polyacrylate," acrylic can be made from Methyl Methacrylate,  Poly Methyl Methacrylate “PMMA”, or a combination of both. It is similar to polycarbonate in composition and often used when an application does not require the impact strength of polycarbonate. For example, headlights use polycarbonate for better impact resistance while taillights utilize acrylic (PMMA) plastic because of its light transmittance capabilities.

Lomont Molding has the capabilities to create individualized high strength structural foam molding products based on your design concepts. Our low-cost molding options allow you to experience the value of structural foam molding at a price point that fits your budget.

Not all plastics are acrylic, although all acrylic materials are classified as plastic. In injection molding, this translates to acrylic as a better choice than other plastics because acrylic plastic maintains its 94% light transmittance per inch without hazing or yellowing. It is also lightweight and cost-effective. These properties make acrylics a popular choice for lighting and medical equipment. Interested in using this material for your project? Request a quote to get pricing.

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The foam injection molding process can be used on many different sized parts to produce a high strength molded part that is lighter in weight. Many large parts require thicker walls than standard injection molding can effectively produce. Structural Foam allows for quicker process and cycle times on thicker parts. This low-cost molding process produces parts that are structurally sound, nearly stress-free and have minimal warpage. Lomont’s structural molding parts are thicker and sturdier than those created with other processes.

If your application requires light transmittance, strength and economy, our customized acrylic plastic injection molding can deliver the long-lasting results you need.

Acrylic becomes liquid at 160 degrees Celsius, allowing the material to be easily injection molded. Like other thermoplastics, acrylic can be heated to the melting point, cooled, and reheated without significant degradation in the material.