| Impact modification | Adds a flexible phase that can deform and help dissipate energy when rigid PVC is struck. | Impact performance at the product’s service temperature, wall thickness, and expected loading conditions. | Notched impact testing, such as ASTM D256 or ISO 180; compare results only when specimen preparation and test conditions match. |
| Weathering suitability | Acrylic-based modifiers are commonly selected for outdoor rigid-PVC applications where weatherability is important. | Color change, surface appearance, and retention of impact performance after exposure; the complete PVC formulation also affects results. | Accelerated weathering using a defined method, such as ASTM G154 or ASTM G155, followed by relevant appearance and mechanical tests. |
| Processing and fusion | Can influence PVC fusion behavior, melt flow, and the balance between processability and finished-part performance. | Extruder output, melt temperature, torque or motor load, surface finish, and consistency at the intended production rate. | Run a controlled processing trial using the same PVC compound, equipment settings, and production conditions. |
| Surface and appearance | A suitable grade can help maintain the surface quality required in rigid-PVC products, but the result depends on dispersion and processing. | Gloss, color, visible defects, and surface consistency in the actual molded or extruded part. | Inspect finished production samples and define acceptance criteria for the application. |
| Typical application fit | Often considered for rigid-PVC building and construction products where impact resistance and outdoor durability are key requirements. | Match the modifier to the product specification, such as profiles, siding, or other rigid-PVC components; do not assume one grade suits every process. | Check the end-product specification and validate performance on production-representative samples. |
| Comparison with other modifier families | AIMs are one option among PVC impact modifiers. CPE and MBS are other established families, each with different performance and formulation trade-offs. | Acrylic grades are often considered when outdoor weatherability matters; MBS grades are commonly used when transparency is important, while CPE grades are used in a range of rigid-PVC formulations. Confirm suitability for the specific product. | Compare equivalent formulations and test conditions rather than relying on modifier-family labels alone. |
| Selection and validation | The “best” modifier is the grade that meets the application’s performance requirements and runs reliably in the buyer’s PVC formulation and process. | Review technical data, recommended handling and processing guidance, formulation compatibility, and lot-to-lot quality controls. | Request current technical documentation and conduct a controlled laboratory evaluation followed by a production trial. |