Flexible PVC compounds and plasticizers
Flexible PVC is a formulated material in which resin, plasticizer, stabilizer and other ingredients produce the required processing and end-use behaviour. Specify a complete compound or a defined formulation ingredient; hardness alone cannot establish equivalence.
General technical information published by PAXOMER Inc. to support preliminary material evaluation. It is compiled from the sources cited on this page and has not been independently reviewed or certified by a professional engineer, laboratory or certification body. Values marked typical, illustrative or requiring confirmation are not specifications. Confirm properties, standard editions, regulatory status and suitability for your specific application with the manufacturer and, where the use is regulated or safety-related, with a qualified professional or the relevant authority.
1. Quick answer
Flexible PVC is a formulated material in which resin, plasticizer, stabilizer and other ingredients produce the required processing and end-use behaviour. Specify a complete compound or a defined formulation ingredient; hardness alone cannot establish equivalence.
2. What is the product, and what function does it perform?
Flexible PVC is a formulated material in which resin, plasticizer, stabilizer and other ingredients produce the required processing and end-use behaviour. Specify a complete compound or a defined formulation ingredient; hardness alone cannot establish equivalence.
3. What types, constructions and grade distinctions are available?
| Family or construction | Selection distinction | Buyer check |
|---|---|---|
| Dry-blend or pellet compound | Prepared formulation for a specified conversion route | Fusion behaviour, uniformity, heat stability and delivered form |
| PVC plastisol | Resin dispersion in a compatible liquid plasticizer system | Viscosity, ageing, deaeration, gelation and fusion |
| General-purpose plasticizer | Candidate balance of flexibility and processing | Compatibility, efficiency and exact-use documentation |
| Specialty plasticizer | Selected for particular volatility, extraction or temperature demands | Evidence in the actual formulation and exposure |
4. Which properties and measurement conditions should the specification include?
| Characteristic | Why it matters | Specification basis |
|---|---|---|
| Hardness | A conditioned specimen response, not a full formulation identity | Scale, thickness, conditioning and ageing |
| Plasticizer content | Depends on the recipe denominator | State phr or mass fraction and the components included |
| Low-temperature behaviour | Depends on plasticizer, resin and finished construction | Method, endpoint and conditioning |
| Migration or extraction | Depends on contact material or liquid and exposure | Time, temperature, specimen and measured change |
5. How is the material manufactured and converted?
Compound production combines controlled ingredient weighing, mixing and, where appropriate, melt compounding and pelletizing. Plastisols require dispersion, ageing control, deaeration and thermal fusion in the actual article. Resin selection and plasticizer solvating behaviour influence the process window.
Extrusion, calendering, coating and moulding impose different heat and shear histories. Adequate fusion must be balanced with heat-stability demands. Do not adopt a universal temperature or residence time from another compound; use the exact-grade processing guidance and plant trial.
6. Which applications and end-use boundaries should be defined?
Potential applications include selected cable constructions, films, coated fabrics, hoses, flooring and seals. Each has different fire, electrical, contact, weathering and durability requirements. No medical, food-contact, cable or construction approval follows merely from the terms flexible PVC or non-phthalate.
7. Which quality controls support qualification?
Qualify the finished formulation for mechanical behaviour, ageing, migration or extraction, colour and processing consistency. Add electrical, flame or product-contact evaluation only where applicable to the intended article. Obtain exact-product SDS, compositional declarations and supporting use documents. A plasticizer declaration cannot approve every other ingredient in the finished compound.
8. How should production problems be investigated?
| Observation | Possible mechanisms to investigate | Trial or control |
|---|---|---|
| Surface tack or exudation | Compatibility, loading, fusion and ageing | Check the complete formulation and contact environment |
| Brittleness after exposure | Plasticizer loss, chemical contact and thermal history | Compare conditioned and aged specimens with mass and mechanical changes |
| Colour change during conversion | Heat history, stabilization and contamination | Record residence conditions and compare a controlled processing trial |
9. What limitations and tradeoffs affect selection?
Plasticizer selection balances process behaviour, flexibility, permanence and compatibility. Low volatility does not establish resistance to every liquid extraction test. Alternative elastomers can offer different performance but change processing and economics. Compare accepted article performance rather than matching only initial hardness.
10. Which market developments require current evidence?
Eastman’s comparison tool explicitly uses a defined plastisol basis for its comparison data. This illustrates why published values need their recipe and test context. Procurement decisions should verify current exact-use requirements and supply documentation instead of inferring blanket suitability from a chemical-family label.
11. Prepare a PAXOMER technical enquiry
PAXOMER is a Canadian technical-supply, manufacturer-development and market-development company. Submit the intended application, current material or construction, process, acceptance criteria, destination and sample requirements. We can assess the technical requirement and potential development path. This guide does not establish stock, a manufacturer appointment or a supply commitment.
12. Primary references and evidence boundary
References establish material-family or test-method scope. They do not establish PAXOMER representation, exact-product performance or suitability of a finished system. Full paid standards have not been reviewed.
Eastman plasticizer comparison tool and stated formulation basis (opens in a new tab)
Eastman flexible PVC application scope (opens in a new tab)
13. Describe fusion, permanence and formulation acceptance as different questions
A plastisol’s flow before heating, gelation during heating and development of a fused article are different stages. Record resin grade, plasticizer system, solids, ageing and the actual heating history. A low initial viscosity alone cannot establish a suitable finished coating or moulded part.
Plasticizer efficiency is tied to a specified formulation and endpoint. Equal phr of different plasticizers need not give equal hardness, fusion or permanence. Define phr against the stated resin mass; a percentage of the total compound is a different denominator.
Volatility, migration into adjacent materials and extraction into a contacting liquid are different loss mechanisms. Compare the relevant exposure, time, temperature, geometry and measured property change. A material described as low migration is not thereby approved for all fluids or product-contact uses.
Compound acceptance should identify the complete recipe or controlled grade, conversion route, appearance, mechanical response, exposure and any applicable product requirements. Regulatory or certification claims belong to the exact finished construction and use, not a general plasticizer family.
14. Describe fusion, permanence and formulation acceptance as different questions: specification and investigation
| Parameter or observation | Technical interpretation | Qualification record |
|---|---|---|
| Plastisol viscosity drift | Ageing, resin/liquid interaction and preparation | Time, temperature, shear history and exact recipe |
| Underdeveloped finished properties | Gelation/fusion and process history | Actual article temperature history and defined property test |
| Surface exudation | Compatibility, loading and exposure | Conditioned and aged specimens with contacting materials |
| Matching hardness but different service | Loss mechanisms and formulation differ | Matched ageing, extraction or contact trial |
15. How should a plasticizer change be assessed beyond initial hardness?
Compare the processed compound after the relevant heat, fluid or migration exposure, using the intended contact material and conditioning. Record plasticizer and stabilizer identities and the complete formulation. Equal initial hardness does not establish the same flexibility retention, processing or destination compliance.
16. Which records distinguish a plasticizer comparison from a hardness comparison?
Use this comparison record to make an enquiry or trial interpretable. It is a buyer worksheet, not a set of material acceptance limits. Agree the exact grade, procedure and decision criteria with the responsible technical team.
| Record | What to document | Comparison condition |
|---|---|---|
| Formulation identity | Record plasticizer, stabilizer and relevant compound ingredients | Compare controlled formulations rather than unspecified PVC |
| Processing | Record fusion/processing observations using the agreed method | Preserve preparation and thermal history |
| Initial properties | Record hardness method, specimen and conditioning | Compare the same test conditions |
| Aging/contact | State contact medium and required retained properties | Assess migration or property change for the intended duty |
17. How does phr differ from weight percent in a PVC compound?
Parts per hundred resin expresses an ingredient relative to 100 parts of resin, not relative to the complete compound. State which ingredients belong in the formulation total and whether each supplied product contains carrier. Converting phr to weight percent is a mass balance; it does not predict hardness, migration, thermal behaviour or regulatory suitability.
Hypothetical calculation: 100 parts resin, 40 parts plasticizer and 10 parts other ingredients total 150 parts. The plasticizer is 40 phr but 40 ÷ 150 × 100 = 26.67% of this complete compound by mass. It is not 40% of the compound. The quantities illustrate notation only and are not a PVC formulation recommendation.
18. What should a flexible-PVC comparison request beyond hardness?
Use the following application-specific comparison record to make the enquiry and qualification decision explicit.
| Decision area | Evidence to request | How to interpret it |
|---|---|---|
| Formulation basis | Resin identity, phr table and delivered ingredient composition | Compare on a declared basis. |
| Initial properties | Hardness method, specimen and conditioning | Match the procedure before interpreting a difference. |
| Exposure | Actual contacting medium, duration and temperature | Request relevant retained-property and migration evidence. |
| Processing | Fusion/processing observations and thermal history | Separate formulation and processing changes. |
A product-specific example: Eastman’s public TDS for Eastman 168 non-phthalate plasticizer lists specific gravity 0.984 at 20°C/20°C and viscosity 66 mPa·s at 25°C. These are properties of that plasticizer, not a finished PVC compound. The TDS describes typical average-lot values, not a guarantee for every shipment. Do not use these numbers as another grade’s properties or as evidence of finished-compound compatibility or regulatory suitability.
19. Why can compounds with equal hardness age differently?
If two compounds show similar initial hardness but perform differently after contact or ageing, do not treat hardness as a proxy for ingredient retention. Review the complete compound identity and actual exposure conditions. Compare initial and exposed properties on the same method and retain any visible surface or mass changes with the test record.
20. Frequently asked questions
Is non-phthalate the same as universally approved?
No. It describes a compositional category; suitability still depends on the exact product, formulation, use and destination.
What does phr mean in a PVC recipe?
Parts by mass per hundred parts of the specified resin basis. It is not the same as weight percent of the complete formulation.
Can equal hardness establish a substitute compound?
No. Migration, ageing, low-temperature response and processing can differ despite similar initial hardness.
Is a plastisol already fully fused PVC?
No. It requires an appropriate thermal process to develop the intended finished structure.
Is low volatility the same as low extraction?
No. They describe different exposure and loss mechanisms.
Can equal phr establish equal plasticizer performance?
No. Compare the same complete formulation and accepted endpoints.
Can initial hardness predict plasticizer retention?
No. Initial hardness and retention after heat, fluid or contact exposure are separate questions.
Should a plasticizer trial identify the contact material?
Yes. Record the actual contacting material or medium, exposure conditions and intended use; do not generalize a result to every contact.
Does 40 phr mean 40% of the finished compound?
No. It means 40 parts per 100 parts resin. The finished-compound fraction depends on every ingredient in the total.
Can hardness alone establish plasticizer compatibility?
No. Initial hardness does not replace processing, contact and ageing evidence.
Is the illustrated phr recipe suitable for production?
No. It is a notation example with hypothetical quantities, not an approved compound design.
21. References
Links inside sections are supplier or standards-body context for the statements they accompany.
Last revised 2026-10-27.
Related guides
Explore further
Product and material pages
Material card: Flexible PVC compounds and plasticizers (listed in Products & Solutions).
Glossary terms
Plasticizer permanence · PVC plastisol · Parts per hundred resin · Plasticizer migration · Plastisol fusion