I coordinate urgent material sourcing for manufacturers, mostly silicone and elastomer projects. Over the last five years, I've placed more than 300 rush orders — some for $150, some for $80,000. This FAQ is the stuff I wish every engineer and small business owner asked before buying Momentive silicones (or any silicone, honestly). It's not a sales page.

Here's the short version: silicone is a material category, not one product. If someone sells you 'silicone' without asking what you're building, run.

What Exactly Are Momentive Silicones?

Momentive is a specialty chemicals and materials company that makes a wide range of silicone-based products. If you've ever used a silicone lunch box, a high-temp gasket, or a weather-resistant sealant, there's a good chance a silicone like Momentive's was part of the recipe. Their portfolio includes liquid silicone rubber (LSR), high-consistency rubber (HCR), RTV sealants, silicone foam, and specialty elastomers. These materials end up in medical device components, EV battery seals, food-contact gaskets, and construction sealants.

According to Momentive's product literature (momentive.com, accessed April 2025), the company supplies both standard and custom silicone solutions for industrial manufacturers. I'm not a chemist, so I can't speak to every polymer detail. What I can tell you from the buying side is that you need the actual datasheet for the specific product line, not a general description of the brand.

Is Momentive the Same as GE Silicones?

Sort of. Momentive has roots in GE Silicones, which is why people still say 'GE silicone' when they mean a legacy specification. That heritage matters because it means there's decades of application data. For an engineer, that's useful. But don't assume a 2025 Momentive product is identical to a GE product from 1995. Formulations change, suppliers improve products, and older test data may no longer apply. When you order, ask for the current technical datasheet and, if the part is critical, a lot-specific certificate of analysis.

Can I Use Silicone Sealant to Attach Foam Board?

This is a mistake I see a lot: people treat silicone sealant like structural adhesive. Silicone is flexible and waterproof, but it isn't a fastener. If you're putting up foam board insulation, the foam board screws carry the load. Don't rely on sealant to hold the board in place.

Use a proper foam board screw — wide threads, corrosion-resistant coating, and the right length for your substrate. Drive it flush, not countersunk too deep. Then seal the seams and screw heads with a low-modulus silicone sealant. That gives you a weather-resistant assembly, with the mechanical strength coming from the screws.

In March 2024, a customer sent me a photo at 4pm showing a foam board wall that had pulled away from a concrete substrate. The screws were too short, and the sealant was doing all the work. We swapped to longer coated screws and used a Momentive silicone sealant for the edges. The rework held fine. The alternative was a $12,000 construction delay.

Are Silicone Bowls Food Safe?

Usually, yes, but only if the supplier actually tests it. A silicone bowl made from platinum-cured, food-grade silicone is typically stable from about -40°F to 446°F, depending on the formulation. That's why silicone is popular for collapsible camping bowls, baby bowls, and bakeware.

Here's the catch. I'm not a toxicologist, so I can't speak to every additive. What I can tell you from the paperwork I've requested from suppliers over the years is that 'food-grade silicone' on a label doesn't always mean there's an FDA 21 CFR 177.2600 letter behind it.

If you're buying silicone bowls for resale, for a commercial kitchen, or for a project that will touch food, ask for a compliance letter and a test report. If the seller hesitates, walk away. It's not paranoia. It's about having a paper trail.

TPU vs Silicone: Which Is Better?

It depends on what you're making. Better is the wrong question. TPU (thermoplastic polyurethane) and silicone are both elastomers, but they behave differently.

TPU tends to be tougher and more resistant to tearing and abrasion. It's a good choice for phone cases, tubing, and pump diaphragms that see mechanical wear. Silicone, on the other hand, handles higher and lower temperatures, as well as a wider range of chemical exposures. It also has a softer hand feel, and in sealing applications it often has better compression set performance.

I've watched a product fail because the team chose silicone for a chute liner that needed TPU's abrasion resistance. I've also watched a product fail because they picked TPU for an engine seal that needed silicone's heat resistance. There's no universal winner. There's only the right material for your operating conditions.

Momentive doesn't make TPU, so this isn't a pitch for silicone. If your design needs silicone, start talking durometer, tear strength, and heat aging. If it needs TPU, talk to a thermoplastic specialist. Either way, get the datasheets before you commit to a mold.

Why Does My Silicone Order Take So Long?

This is the question nobody thinks to ask early enough. LSR and HCR are often manufactured in production lots. If your spec is common, a distributor might have it in stock. If you need a custom color, a special cure system, or full compliance documentation, lead times can run six to twelve weeks. That's the reality.

Can you rush it? Sometimes. In Q1 2025, I asked several suppliers for expedited silicone production. The rush fees ranged from 10% to 20% of the base order, and one quote had a 35% markup because it required a line change and new QC documentation. Sound expensive? It is. But the alternative was a production line sitting idle.

I learned this in 2022, after we lost a $10,000 order because we waited too long to order material. My current policy is to book the raw material before the mold is finished. It feels backwards, but it eliminates the last-minute panic.

What Should I Ask a Supplier Before Ordering Momentive Silicone?

This is the FAQ within the FAQ. Before you send an RFQ, ask these four things:

First, is the standard product in stock, or is it made to order? Second, what is the cure system, and does it match your production process? Third, can they supply the current technical datasheet and a certificate of analysis? Fourth, what is their return policy if the batch fails incoming inspection?

A supplier who can't answer those questions is a supplier who doesn't actually know their product. That's a bigger risk than a longer lead time.

Do Small Silicone Orders Get Real Support?

They should. This is the place where I'm openly opinionated. Small orders are not a reason to treat a customer badly. When I was starting out, the vendors who took my $200 order seriously are the ones I still called for $30,000 orders.

Momentive is a large manufacturer, so most small teams won't buy direct. You'll work with a distributor, and the distributor matters more than the raw material brand. If a distributor says 'too small' or 'we don't do test quantities,' that's a red flag. There are distributors who welcome a 1kg sample order, because they know it can grow.

Small doesn't mean unimportant. It means potential. If you're a startup testing a new silicone bowl design, a 5kg material order is a legitimate need, not a waste of anyone's time. A good supplier will treat it that way.