ISBM materials / Material assessment
rPET Injection Stretch Blow Molding
rPET injection stretch blow molding requires a defined recycled feedstock, a traceable batch and a bottle-specific trial. Recycled PET is not a single interchangeable specification: resin, flakes, recycled-content blends and intended applications can differ. Evaluate intrinsic viscosity, moisture, contamination and color alongside the proposed preform and process. Keep material processing feasibility separate from food-contact authorization and finished-package compliance. No recycled-content percentage or ISBM Machine compatibility is guaranteed here.
Discuss your material and bottleWhat exactly is the recycled feedstock?
Indorama Ventures lists recycled flakes and resins with different specifications and intended applications. Its portfolio includes products for bottle use and other uses, demonstrating why the term rPET alone is not a sufficient material definition. Identify the supplier, grade, feed form, source, lot and declared recycled-content basis.
Record whether the proposal uses a supplied recycled-content resin, a controlled blend or another feed arrangement. Do not assume that a flake product and a pelletized bottle resin can be processed on the same configuration without assessment. A source or formulation change needs a documented review.
Which incoming-material evidence matters?
IV and moisture
Request the supplier’s intrinsic-viscosity specification, method and batch result, together with the relevant moisture and preparation requirements. Do not impose an unsupported universal limit.
Contamination
Identify the supplier’s contamination controls and test records. Define the project-specific acceptance criteria and the response to nonconforming material.
Color and appearance
Agree the measurement or approved sample reference. Keep color, haze and visible defects linked to the lot and molding conditions.
Consistency
Compare more than one supply lot where production qualification requires it. A single successful sample does not establish ongoing batch consistency.
rPET incoming-material evaluation record
| Evaluation item | Evidence to record | Decision |
|---|---|---|
| Identity and source | Supplier, grade, feed form, lot and recycled-content declaration | The tested supply can be reproduced |
| IV | Specification, method and lot measurement | The material fits the agreed development basis |
| Moisture and preparation | Supplier requirements and measured condition before processing | The process starts from controlled feedstock |
| Contamination and color | Relevant supplier tests and agreed appearance reference | Risks are assessed against the intended bottle |
| Filtration and equipment | Actual preparation and melt-handling arrangement | Any required system changes are explicitly reviewed |
| Trial and final use | Preform results, bottle tests and separate use-compliance documents | Process feasibility is not confused with legal authorization |
How should filtration and molding trials be approached?
Define the equipment boundary before a trial. Record where material preparation and any filtration occur, what equipment is proposed and what evidence supports the arrangement. Do not promise that a standard injection unit removes every contaminant or can accept an unspecified recycled feed.
Evaluate the preform and finished bottle against the agreed drawing and quality criteria. Link each sample to its lot, preparation, process settings and tooling. If defects change between batches, retain that traceability before changing the process or accepting the supply. This is a material-feasibility record, not a complete factory quality-system procedure.
Does recycled origin establish food-contact suitability?
No. Recycled-content evidence, processability and food-contact suitability answer different questions. Obtain applicable supplier documentation for the exact resin and intended use, then review the finished package and target market with qualified regulatory support. Do not generalize a supplier’s authorization for one product, recycling process or use to every rPET supply.
Likewise, a recycled-content percentage does not by itself substantiate carbon savings or recyclability of the final package. Keep such claims outside the equipment assessment unless they have their own supporting evidence.
Prepare an ISBM material assessment
Send the current supplier data sheet, batch records, feed form, proposed recycled-content composition and bottle drawing. State the appearance, contents and use requirements. The assessment should define a controlled trial and any equipment-interface questions, not promise compatibility merely because the underlying polymer is PET.
Material assessment questions
Are recycled flakes and rPET resin interchangeable?
No. Their form, preparation, specifications and intended processing route need separate assessment.
Does one good trial approve all future lots?
No. Define the supply controls and repeat assessment needed when material composition or batch characteristics change.
Does successful molding prove food-contact approval?
No. Processing feasibility and applicable use-compliance evidence must be reviewed separately.
Supplier references
Resin references describe material information, not completed trials on our equipment. Review the current grade documents for your project.
Discuss Your ISBM Bottle Project
Send the exact resin grade, supplier documents, bottle drawing and intended use. Include material batch records or existing trial reports when available.
The assessment should define the evidence needed for your material and container. It is not a guarantee of compatibility, output or regulatory approval.