Food Grade Polyisobutylene (CAS 9003-27-4): What It Is, Applications and Buying Guide

Food grade polyisobutylene (CAS 9003-27-4, also written polyisobutene or PIB) is a non-toxic, colorless and odorless polymer made by cationic polymerization of isobutylene. It is approved for food-contact use and is supplied in high-activity and low-activity grades, each matched to a different set of applications. The product comes from Shandong Hongrui New Material Technology Co., Ltd. and ships with COA, MSDS and export documentation.

What Food Grade Polyisobutylene Is

Polyisobutylene is a hydrocarbon polymer built from isobutylene monomers. The food grade cuts the fraction that clears food-contact standards: no residual catalysts that migrate, no odor, no color. What is left is a stable, tacky polymer that does not react with the materials it touches.

Parameter	Typical value
CAS No.	9003-27-4
Molecular formula	(C4H8)n
Grade	Food grade, high-activity and low-activity
Appearance	Colorless, odorless, transparent viscous liquid
Molecular weight	Grade-dependent; confirm against the COA for your application
Solubility	Soluble in aliphatic and aromatic hydrocarbons; insoluble in water
Food-contact status	Non-toxic, approved for food-contact applications

Key Properties That Matter in Practice

• Chemical stability. Resists heat, light, oxygen, acids and alkalis far better than most natural rubbers, so a batch on your shelf behaves like the batch you certified.
• Low gas and vapor permeability. This is why it shows up in flexible packaging and sealing layers where moisture or aroma control decides the product.
• Wide-temperature tackiness. Stays tacky and flexible from cold storage to processing temperatures, which matters for chewing gum base and plasters.
• Compatibility. Blends cleanly with butyl rubber, paraffin wax, resins and plasticizers, so you can tune hardness without re-working the formula.
• Two activity grades. High-activity PIB carries reactive double bonds for further chemistry; low-activity PIB is inert and preferred where the polymer itself is the performance layer.

Where Food Grade Polyisobutylene Is Used

Chewing gum base and confectionery

• Gum base at standard and sugar-free formulations
• Chewy and coated tablet joints

Medical and wound care

• Medical plasters and dressings
• Ostomy bags and pharmaceutical rubber stoppers

Packaging and hot melt

• Packaging materials and film layers
• Hot melt adhesives and joint compounds

Sealants and industrial mastics

• Grease and lubricating grease
• Surfboard wax and protective mastics

If your application is not on this list, send the spec: the same polymer family covers a wider range than the standard datasheet shows.

Product FAQs Before You Order

Is food grade polyisobutylene safe to use?

Yes for food-contact use. The grade is non-toxic and odorless by design, and each batch ships with COA and MSDS. Ask for the food-grade statement when you confirm the order.

High activity or low activity - which do I need?

High activity is the reactive grade (fuel and lubricant additives, dispersant chemistry). Low activity is the inert performance grade (adhesives, sealants, packaging). Send your application and we will match the grade; free samples allow you to verify first.

What documents come with the shipment?

COA per batch, MSDS and the required export documents. Third-party inspection (SGS, Intertek, BV) is accepted on request before loading.

Do you support sample requests?

Yes. Give the target application, preferred grade and quantity, and we quote samples with COA so you can test before committing.

What is the lead time?

In-stock items dispatch in 3-7 days. Production orders typically run 15-30 days depending on grade and volume.

Can buyers visit or arrange a factory audit?

Yes. Sales and technical teams support audited buyers; contact us through the contact page to arrange.

Need a quote or a technical datasheet for food grade polyisobutylene? See the product page or browse the food additives category.