Polyvinyl chloride (PVC) has become one of the general-purpose resins with the lowest cost and the highest dosage due to its excellent chemical properties and physical and mechanical properties. PVC can be processed using various major processing techniques such as extrusion, compounding, injection molding, and blow molding.

The thermal decomposition temperature of PVC is close to its processing temperature, so it is necessary to add heat stabilizers, plasticizers, impact modifiers and processing aids and other additives.

The processing performance of PVC is not very good, and the processing aid is very unique. Only a small amount can be added to greatly improve the processing performance of PVC.

Extrusion is the most widely used PVC processing technology: window frames, window panels, rain gutters, pipes, cables, transparent and opaque sheets, etc.

A variety of different types of extruders are used in molding processing, and sometimes even processing the same product in the same place will use a variety of extruders such as single screw extruder, parallel twin screw extruder and conical twin screw extruder. Therefore, when designing formulations, the limitation of processing conditions becomes smaller.

The addition of acrylic processing aids to PVC formulations facilitates this extruder flexibility and controls the physical properties of the final product.

Processing aids are useful for:

· Melt elasticity and outlet expansion increase with increasing molecular weight of processing aids. The extruded material fills the cavity well and contacts the cavity walls evenly.

Processing aids are useful for:

· Melt elasticity and outlet expansion increase with increasing molecular weight of processing aids. The extruded material fills the cavity well and contacts the cavity walls evenly.

- Due to the rapid cooling of the melt and the high elasticity, the shark skin phenomenon is reduced or even disappeared.

· The surface gloss is improved, especially when the mold release series additives are used together with other high molecular weight series additives.

· Higher friction in the melt leads to a decrease in "fish eyes" in transparent PVC and ductile PVC.

The extrusion process of rigid PVC foam materials has strict requirements on the physical and mechanical properties of the melt: if the melt does not have sufficient strength, the bubbles will burst or transfer to the surface, resulting in high density, irregular cell structure, and Surface unevenness etc.

Therefore, this application requires the use of high levels of processing aids in the formulation.

The benefits of processing aids are:

When the system contains acrylic processing aids, the melt strength will be greatly improved: bubbles will remain in the melt, so that low-density foam materials can be obtained;

· Microcells will not break, and a fine regular structure can be obtained.

· Since no gas escapes from the melt, the surface of the material is particularly smooth and shiny. This is especially true for free-foam panels used as display signs.

· Acrylic processing aid brings high elasticity and die expansion to the melt: As a result, it is the only additive grade suitable for forming thick-walled products and reducing the voids between inward and inward cells.