Direct comparison
Polyolefin vs Polyethylene: Family vs Member
Polyolefin vs polyethylene: PE is one polyolefin. Compare how FDA's 21 CFR 177.1520 groups PE, PP and copolymers, with densities, and where PVC fits.
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How do Polyolefin (family), Polyethylene (member) compare side by side?
The table below compares Polyolefin (family), Polyethylene (member) across 11 procurement-relevant dimensions, from what the term means through source.
Side-by-side comparison
| Dimension | Polyolefin (family) | Polyethylene (member) |
|---|---|---|
| What the term means | A family of polymers made from olefin (alkene) monomers; polyethylene and polypropylene are its most common members (Polymershapes, read 2026-10-30). | One polymer: basic polymers made by the catalytic polymerization of ethylene (21 CFR 177.1520(a)(2)(i)). |
| Relationship | The broader category. | A single member of that category. Every polyethylene is a polyolefin; not every polyolefin is polyethylene. |
| Members FDA lists under "Olefin polymers" | Polypropylene, propylene homopolymer, polyethylene, fumaric acid-grafted polyethylene, olefin basic copolymers, poly(methylpentene), polyethylene graft copolymers and ethylene-maleic anhydride copolymers (21 CFR 177.1520(a)). | Listed in (a)(2): plain polyethylene and fumaric acid-grafted polyethylene. Polyethylene graft copolymers are listed separately in (a)(5). |
| Starting monomers named in the regulation | Propylene, ethylene, other 1-alkenes of 2 to 8 carbon atoms (for the copolymers) and 4-methylpentene-1. | Ethylene only. |
| Density range in the FDA table | Varies by member: 0.880-0.913 for polypropylene and propylene homopolymer; 0.85-1.00 for polyethylene and for olefin copolymers in item 3.1a (no units given in the table). | 0.85-1.00 for each polyethylene item (2.1 to 2.3). |
| Melting point in the FDA table | Polypropylene 160-180 degrees C; propylene homopolymer 150-180 degrees C. | The table gives no melting point for the polyethylene items. |
| n-Hexane extractables limit (food-contact specification) | Polypropylene and propylene homopolymer: 6.4 percent at reflux temperature. | General food-contact articles: 5.5 percent at 50 degrees C; articles for packing or holding food during cooking: 2.6 percent at 50 degrees C; component of food-contact coatings: 53 percent at 50 degrees C. |
| Where PVC fits | Not listed under 21 CFR 177.1520. Vinyl chloride copolymers have their own sections: vinyl chloride-ethylene copolymers (177.1950) and vinyl chloride-propylene copolymers (177.1980). | Polyethylene is made from ethylene alone, while 177.1950 covers copolymers of vinyl chloride and ethylene, listed apart from the olefin polymers. |
| Reading a product label or spec sheet | "Polyolefin" alone does not say which polymer is meant: it can refer to polyethylene, polypropylene or a copolymer. Look for the specific material named on the spec sheet or instructions for use. | Names the specific polymer, so the ethylene-based material is unambiguous. |
| When to pick each term | Use "polyolefin" when you mean the family (for example, polyethylene and polypropylene together) or when a label does not name the polymer. | Use "polyethylene" when the material is specifically ethylene-based. |
| Source | 21 CFR 177.1520, 177.1950 and 177.1980 (law.cornell.edu/cfr/text/21/177.1520, /177.1950, /177.1980), read 2026-10-30; polymershapes.com/polypropylene-versus-polyethylene/, read 2026-10-30. | 21 CFR 177.1520(a)(2) and the paragraph (c) table (law.cornell.edu/cfr/text/21/177.1520), read 2026-10-30. |
Common questions
Common questions about Polyolefin (family) vs Polyethylene (member)
Is polyethylene a polyolefin?
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Yes. Polyethylene is made by the catalytic polymerization of ethylene, and FDA lists it together with polypropylene and olefin copolymers under the single heading "Olefin polymers" in 21 CFR 177.1520 (read 2026-10-30).
What is the difference between polyolefin and polypropylene?
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Polypropylene is one polyolefin, made from propylene (21 CFR 177.1520(a)(1)). "Polyolefin" is the broader family that also includes polyethylene and olefin copolymers. In FDA's table, polypropylene has a density of 0.880-0.913 and a listed melting point of 160-180 degrees C, while the polyethylene items have a density of 0.85-1.00 and no listed melting point.
Is PVC a polyolefin?
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PVC is a vinyl chloride polymer, not one of the olefin polymers FDA lists in 21 CFR 177.1520. FDA treats vinyl chloride copolymers in separate sections, for example 177.1950 (vinyl chloride-ethylene) and 177.1980 (vinyl chloride-propylene), as read on 2026-10-30.
Going deeper
