Can Preventing Plastics Corrosion Increase Flammability Risk?

Exposed wires in an corroded appliance power cord presenting a fire risk

The word “corrosion” is inextricably linked to metals. The all too familiar resulting rust is an eyesore at best and a safety hazard at worst. In some instances, plastics are considered a logical workaround since they don’t rust; but, there’s another truth that cannot be ignored: plastics also corrode.

Like metal, plastics are subject to disruptions in chemical composition caused by moisture or other environmental factors. Unlike metal, though, which oxidizes in response to these disruptions, plastics deteriorate or dissolve. Plastics may not show evidence of corrosion as quickly as metal, but the deterioration weakens the material’s physical and mechanical properties which interferes with performance. This can lead to plastic parts and products being compromised — if not prone to outright failure.

That’s not good news for those in the plastics industry. Plastics corrosion has been around for as long as there have been compounds, but advancements in materials over the past decade have renewed interest in how to prevent it. This is especially critical as it relates to flame retardancy and heat stabilization.

Adding to the Problem?

As plastics become thinner and tasked with more powerful workloads, proper insulation is at risk. The flame retardancy that the walls of a comparatively thick 1mm component offered in bygone days is now proportionately diminished in new designs that are much thinner. Electrical conductivity is at closer quarters, and insulation is more challenging.

Corrosion can greatly diminish the electrical insulation of engineered thermoplastics. Arcs sometimes occur, causing errant transfer of current, charge, or electricity in an instant. That said, while catastrophic failure is possible, it’s also largely preventable.

Custom compounders employ any number of additives to act as flame retardants. For instance, additives that contain chlorine, or bromine are excellent for flame retardancy — but they can also create the risk of corrosion, ultimately compromising protection.

The same holds true for heat stabilizers. Plastics exposed to high heat for extended periods of time will readily corrode without the use of metallic ions such as copper in the case of nylons. The thermal properties of metal extend the life of plastics in exceedingly hot environments or under continuous use. But, like flame retardants, the same elements that provide heat stability to plastics also hasten corrosion.

The Plastics Paradox

This duality sets up a paradox. On the one hand, there is a need for flame retardants and heat stabilizers. On the other hand, there is a need to minimize plastics corrosion.

Halogenated materials address the first need, but run contrary to the second. Not using traditional additives for flame retardancy and heat stabilization isn’t realistic. While omitting them would slow plastics corrosion, it would also increase fire hazard risk.

So, which need takes precedence? As contradictory as it seems, some custom compounders are capable of bridging the gap between competing priorities.

Non-Halogenated Material: The Organic Alternative

The answer lies in non-halogenated materials. These electrically friendly plastics lack the traditional flame retardants and additives used for heat stabilization, processing aids, and mold release agents. Instead, they are formulated with non-halogenated flame retardants and organic heat stabilizers. The specially formulated compounds are exceptional at minimizing corrosion and maximizing performance.  

Teknor Apex is committed to helping its customers and OEMs across industries realize the benefits of non-halogenated plastics. Several key Teknor Apex product lines are built around electrically friendly solutions, including these trusted engineering thermoplastics:

Further, Teknor Apex brings together a unique combination of electrically friendly flame retardants, heat stabilizers, and process aids. As a result, we are well positioned to develop and advance non-halogenated material.

Along with existing non-halogenated options, each new grade Teknor Apex is putting on the market contains no additives that are subject to plastics corrosion — including solutions containing colorants. We work with a select network of colorant suppliers that help us formulate solutions that do not contain potentially corrosive materials.

Plastics corrosion is largely preventable. Leaning into solutions that manage and minimize its impact takes the forward thinking and materials expertise of a customer compounder like Teknor Apex. Learn more in Teknor Apex Materials Solutions: Electrical and Electronics Applications. Click the button below to download your copy of this valuable reference guide.