PU Binder in Rebonded Foam Production: What It Does

PU binder is the material that makes shredded foam hold together. On its own, a pile of foam chips stays a pile of foam chips — compression alone does not create a usable block. Add binder, mix it through the chips, compress the mix and let it set, and you get rebonded PU foam that can be cut, stacked, shipped and used. This article explains what PU binder does in rebond production, how the process works, what to ask us before buying, and why sourcing binder and graded scrap from one supplier is usually simpler.

What PU binder does in rebonded production

Rebonded PU foam is made with recycled PU foam and is 100% recyclable. The feedstock is scrap: offcuts, trimmings, skins, old foam and other graded material. Before it can become a block, that scrap has to be reduced to chips.

Chips do not bond to each other through compression alone. PU binder creates adhesion between chip surfaces so the compressed mass holds as one piece. It is the difference between a loose raw material and a saleable product — for example, a rebonded block or cut sheet for replacement of virgin foam, furniture padding, farming mattress, domestic mattress or modular autoparts.

The finished foam's density and feel come from the combination of chip mix, compression and binder. Change the chip grade or the binder and the output changes. Binder selection is therefore a production decision, not just a purchasing line item.

How the process works

Rebond lines differ in equipment and scale, but most follow the same sequence:

• Sort and grade incoming scrap — for example Grade AA, Grade A or Grade B — and separate memory visco scrap, shredded foam and other types.
• Reduce the scrap to chip size by shredding or grinding.
• Blend the chips to suit the target product.
• Add PU binder and mix until it is distributed through the chip mass.
• Form and compress the mix, in a mold or on a continuous line, into a block or sheet shape.
• Let the binder set so the block holds its shape.
• Cut, slice or peel the block to the thickness and shapes ordered. Shape cutting is supported for rebonded foam products.

Two things matter most at the binder stage: how evenly the binder is distributed, and whether the chip mix is consistent from batch to batch. Uneven distribution shows up later as weak spots during slicing. A shifting chip mix shows up as density variation between blocks.

What the binder has to do

A workable binder should hold chips together through compression, handling and cutting, and keep holding through normal transport and storage. It should also suit the scrap you actually run. Memory visco scrap, shredded foam, Dali skin foam and shoe foam scrap behave differently in a mix, so binder and chip mix need to be matched to each other.

Binder is not a fix for poor feedstock. Skin content, contamination and chip size all affect the finished block. Grade AA, with around 5% skin or a 0-skin version at 20-30kg/m3 density, is a super-good, higher-priced grade. Grade A comes in 5% skin and 15% skin versions, and Grade B carries around 15% skin. Grade choice is a cost-versus-performance decision that sits upstream of the binder.

What to ask us about PU binder

• Which foam scrap grades and chip types is this binder intended for?
• How does it behave when the mix includes memory visco scrap or fine shredded foam?
• What are the recommended storage and handling conditions?
• How is it packaged, and in what quantity per pack?
• What handling and safety information is available?
• What do you recommend if our chip mix or target density changes?
• Can we test a sample against our own scrap before committing to a full order?

Ask us for answers in writing. A binder that performs in one plant can behave differently in another when the chip mix differs.

Why we supply binder alongside graded scrap

We supply PU binder and graded foam scrap from the same operation. The practical benefit is matching: you can discuss binder and scrap together with one contact. You can order binder together with Grade AA, Grade A or Grade B scrap, black, white or mixed colors, shredded foam, memory visco scrap, 10mm thick foam carpet underlay, filter foam scrap, Dali skin foam, Hi-Poly shoe foam scrap (50-60 density), crushed fabric bra foam scrap and old used foam.

Supply, logistics and how we operate

Dongguan Fungbillion Furniture Material Co., Ltd. operates from ChaoLang Industrial Zone, Chashan Town, Dongguan City, Guangdong, China. We are a manufacturer and trading company with an Alibaba-listed supply ability of 5000 Ton/Tons per Month. Foam scrap ships in bales of 200-300kg at a density of 15-30kg/m3. Ports are Shenzhen or Guangzhou. A 40ft container loads 18000-22000kg, and one 40HQ loads 20-22 tons of AA-grade compression bales.

Payment terms include T/T, L/C, D/P D/A, MoneyGram, Credit Card, Western Union and Cash. Main markets are the Middle East, South America, Southeast Asia, Africa and the domestic market.

Our Alibaba shop carries the '13 YRS' badge. 'Onsite Check' is an Alibaba badge, not a product certification. These are Alibaba platform badges, not product specifications or service commitments. The same listings show 'Response Time ≤9h' and 'on-time delivery ≥100%', which are historical platform metrics, not a service promise. Both Alibaba product pages show 'No reviews yet'.

What to tell us when you inquire

Send the finished product you are making (for example, replacement of virgin foam, furniture padding, farming mattress, domestic mattress or modular autoparts), the scrap grade or grades you want to run, your target density, the chip types in your mix, your required quantity and your destination port. Contact Ms. Vicky Chen, Sales Manager — office tel 0086-0769-81805003, mobile 0086-15875576145, WhatsApp 15875576145, email [email protected] — or send the details through our contact page.

Keep reading

For how binder fits the wider process, see the PU binder guide. For how grades differ, see foam scrap grades explained.