Many flexible PVC products are used at different temperatures throughout the year. A seal that is flexible in summer may stiffen in winter; an outdoor cable may be hard to bend at low temperatures. In such products, how the formulation behaves in the cold becomes decisive. DOA, known for helping PVC stay flexible at low temperatures, is often considered for these products. This article summarises where DOA is used in cold-environment PVC products.
Why does PVC stiffen in the cold?
Without plasticizer, PVC is a rigid polymer. A plasticizer works its way between the PVC chains and makes the material flexible. As the temperature drops, the chains move less and the material tends to stiffen. The type and level of plasticizer affect the temperature at which this stiffening becomes noticeable. With its aliphatic structure, DOA helps PVC keep its flexibility at low temperatures.
Cables and cable sheathing
Cables used outdoors, in cold stores or in winter conditions must still bend at low temperatures. In flexible PVC formulations for cable insulation and sheathing, DOA can be considered as a secondary plasticizer to support cold flexibility. In cable applications, electrical properties and related technical requirements are also considered separately in the formulation.
Cold stores and refrigerated environments
Flexible PVC parts used in cold stores, refrigerated areas and unheated spaces in winter must keep working at low temperatures. A part that stiffens in these environments is harder to use and may deform at its bending points. DOA can be considered in the formulation of such parts to support their behaviour in the cold.
Seals and profiles
Door and window seals, refrigerator seals, cold-room door seals and flexible profiles must keep sealing and flexing at low temperatures. In the formulation of such parts, DOA is considered as a component supporting cold flexibility. The seal’s environment and requirements determine the choice of plasticizer.
Outdoor and winter products
Snow and rain gear, outdoor covers, winter sports accessories and other flexible PVC products used in cold climates are also among the areas where DOA is considered. For these products, suitability for outdoor conditions matters as well as cold flexibility.
Artificial leather and coatings
In artificial leather and coated fabrics expected to stay soft in cold weather, DOA can be used as a secondary plasticizer. We cover this separately in our article DOA in Artificial Leather and Coated Fabrics.
Formulation points
- Ratio: the DOA level is set according to the cold flexibility need and confirmed by trial.
- Combined use: DOA is usually used together with a general-purpose plasticizer such as DOTP.
- Volatility and migration: these should be assessed per application.
- Testing: cold flexibility should be checked with tests that match the product’s real conditions of use.
We explain the logic of using DOA with DOTP in our article DOA and DOTP Blends.
Clarifying product requirements
In cold-environment applications, it is important to clarify the conditions of use before starting formulation work. What temperature range will the product work in? Will it be exposed to bending or impact? Will it be used outdoors? The answers help determine the choice and level of plasticizer.
Once the requirements are clear, trial recipes are tested against these conditions. Test methods and acceptance criteria are set according to the product owner’s own standards. Sharing your application and estimated consumption makes the DOA quote process easier.
Frequently asked questions
In which products is DOA used most?
It is often considered for cables, seals, profiles and outdoor products that must stay flexible in the cold.
How much does DOA improve cold flexibility?
The result depends on the formulation, the ratio and the other components. It should be assessed for your product through trials and tests.
Conclusion
DOA is a phthalate-free plasticizer that helps PVC cables, seals and profiles used in cold environments stay flexible. See our DOA plasticizer page for details, and send your application and approximate quantity via the quote form.