H.D.Plastics is a premier supplier for Rigid and Flexible Custom Extruded PVC profiles. Our technical staff can modify the material properties by adding functional additives to achieve high features such as anti-aging properties, UV resistant, corrosion-resistant, high strength to meet customer-specific applications.
Plasticizers for plastics are additives, most commonly phthalate esters in PVC Extrusion application. Plasticizers make it possible to achieve improved compound processing characteristics, while also providing flexibility in the end-use
product. such as PVC, the more plasticizer added, the lower their cold flex temperature will be. Plastic items containing plasticizers can exhibit improved flexibility and durability. Plasticizers can become available for exposure due to migration and abrasion of the plastic since they are not bound to the polymer matrix.
Today we will discuss the degree of plasticization in the production process of PVC extruded profiles and tubing.
1. The influence of the degree of plasticization on PVC extrusion parts performance
The performance of the PVC extrusion profile or corner section profiles is closely related to the degree of plasticization. The lower plasticization, the more brittle of PVC angle profile parts; if the plasticization is too high, the product will appear yellow lines with unqualified properties. Excessive or too low degrees of plasticization will affect the physical and other properties of the products. The degree of plasticization of PVC extrusion product is between 60% and 70%
1. When the degree of plasticization is 60%, the tensile strength is the highest;
2. When the degree of plasticization is 65%, the impact strength is the highest;
3. When the degree of plasticization is 70%, the elongation at break is the highest;
For the production of water supply PVC tubing materials, The appropriate the plasticization degree is between 60-65%. it can reflect the two properties of tensile strength and impact strength in this range.
2. The influence of temperature on plasticization
Polymer materials cannot be melted when the temperature is lower than 80℃, and are in a glassy state. The materials in the glassy state are brittle and hard to be processed in this state; as the temperature rises to 160℃, the materials are highly elastic However, the material still cannot flow in this area. It can only make the material softer and increase the viscoelasticity; the temperature should be between 160-200℃ for PVC melt processing and fluidity, but for any The stabilizer, when the temperature is higher than 200℃, the material will decompose after long-term heating.
Therefore, when controlling the degree of plasticization, the temperature can only be controlled between 160-200°C. Within the temperature difference range of 40°C, when the temperature of PVC is set between 170-180°C, the plasticization is better.
3. Ways to Increase the degree of plasticization
1. By increasing the temperature of the extruder body and screw.
2. Increase the feeding speed of the feeder to increase the degree of plasticization
3. Increase the speed of the extruder when the rated speed of the extruder meets the requirements of the feed.
4. Give the dry powder a good maturation period (12-48h)
The role of maturation
3.1. Eliminate static electricity and reduce pollution
3.2. Increase apparent density
3.3. Improve the degree of plasticization
3.4. Low-molecular-weight polymerization is uniformly dispersed to prevent unstable extrusion.
3.5. Increase the degree of plasticization by reducing the temperature of the confluence core.
H.D. plastics is an integrated engineering and manufacturing solution provider focusing on Plastic Extrusion Profiles & Plastic Tubing for more than 10 years with ISO Certified in China. We combine the industrial experience and expertise to satisfy the challenges of your custom plastic extruded product.