Select a polypropylene grade by defining the converting process and the part’s performance priorities, then comparing homopolymer, random copolymer and impact copolymer candidates. Check melt flow with its test temperature and load, and validate the proposed grade in the intended process before substitution.

PANTEX reviews PP polypropylene enquiries for moulding, packaging conversion and extruded components. Provide the current grade or application brief so the offered material can be assessed against your needs.

Homopolymer, random copolymer or impact copolymer?

Use the family choice to narrow the search, then compare specific grades:

  • Homopolymer: consider candidates where stiffness and heat performance are key priorities.
  • Random copolymer: assess grades where clarity, appearance or sealing requirements are important.
  • Impact copolymer: assess candidates where toughness, including at lower temperatures, is a priority.

LyondellBasell’s polypropylene selection guidance discusses these trade-offs and the importance of process and part requirements. Its separate random copolymer and impact copolymer pages describe the optical and impact priorities of those families. These producer references provide selection context, not a PANTEX affiliation or a guarantee for every grade.

How should melt flow be compared?

Record whether the result is melt mass-flow rate (MFR) or melt volume-flow rate (MVR), together with units, temperature, load and test method. ISO 1133-1:2022 addresses both measurements under specified conditions. They are different quantities; a numerical match is not enough to establish equivalence.

Use the process as the starting point: a thin-wall injection-moulding brief and an extrusion brief can need different flow behaviour. Ask the converter to assess filling, dimensional consistency, appearance and mechanical performance during trials. Do not approve an alternative solely because its headline MFR matches the incumbent grade.

Define the part’s acceptance requirements

Separate essential limits from preferences in the RFQ:

  • Stiffness, impact performance and the temperatures at which they matter.
  • Dimensions, wall thickness, assembly features and allowable variation.
  • Colour, gloss, clarity or surface requirements.
  • Heat exposure and contact with the intended contents or environment.
  • Additives, reinforcement and permitted recycled content, where specified.

ISO 19069-1:2015 provides a PP designation system. Use a full producer grade and agreed datasheet revision alongside any designation. Require test methods and conditions for contractual values, and distinguish typical properties from guaranteed limits.

Does “PP” establish food-contact suitability?

No. If the end use involves food contact, identify the destination and conditions of use and request the necessary documentation for the offered formulation. Have the responsible compliance team confirm applicability before release.

Can another PP family replace the existing grade?

Only after a technical comparison and process qualification. The family change may affect several properties even when one reported value is similar. Retain approved samples and the agreed release criteria.

PP RFQ checklist

  • Existing grade, application and converting process.
  • Homopolymer or copolymer preference, if already established.
  • Flow requirements with units, temperature and load.
  • Mechanical, thermal, appearance and dimensional criteria.
  • Datasheet, SDS, declarations and qualification requirements.
  • Quantity, packaging, destination, delivery terms and timing.

Request a PP quotation. For related polyolefin enquiries, see the HDPE grade-selection guide. Availability and final supply terms are confirmed for the proposed grade.

References reviewed on 20 September 2026.