Vinyl Foam Processing Aids

Introducing SURECEL™ 488 Processing Aid

The Dow Chemical Company is offering a new acrylic processing aid designed for foamed PVC applications. SURECEL™ 488 improves the processing of PVC foam by reducing the viscosity and improving the flow characteristics of the molten polymer.
 

• Low-density capability for cellular PVC
• Lower use cost due to increased efficiency of ultra-high molecular weight
• High melt strength and elasticity
• Excellent expansion from die

The table below compares different generations of vinyl foam processing aids to SURECEL™ 488 processing aid.
 

	PARALOID™ K-445	SURECEL™ 467	SURECEL™ 488
Molecular Weight	+	++	+++
Loading Level (PHR)	9	7	5
Extrusion Torque (G-m)	4643	4716	4431
Melt Pressure at the Die (psi)	1137	1230	1134
Melt Pressure at Screw Tips (psi)	1442	1554	1428
Melt Temperature (ºC)	172	172	173
Time to Floor* (s)	46	53	48
Relative Foam Expansion**	100	111	101
Relative Foam Density**	100	99	103

_{^*Time to Floor is a recording of the time it takes the extrudate to travel from the die to the floor. This distance is 44.5 inches. A longer time to the floor is indicative of higher melt strength.}

_{**Density and expansion data points are reported relative to the performance of PARALOID^TM K-445.}

According to the aforementioned statistics, SURECEL™ 488 can be utilized at a higher loading rate while exhibiting comparable foam expansion and density performance. At the specified relative efficiency levels, SURECEL™ 467 moderately outperforms SURECEL™ 488. However, it is worth mentioning that the full performance of SURECEL™ 488 cannot be displayed on this lab-scale extrusion equipment. Due to its ultra-high molecular weight, SURECEL™ 488 needs extra time to detangle completely and evenly disperse throughout the PVC melt. The suggested full efficiency is reached when the material is processed at the manufacturing level, where extruders have longer residence durations and more vigorous mechanical mixing.

Similar Fusion Characteristics
SURECEL™ 488 offers similar drop-in replacement even at a lower level of dosage. 

 

Density and Expansion
SURECEL™ 488 is ~ 50% more efficient than PARALOID™ K-445.
 

Melt Rheology
SURECEL™ 488 as an ultra-high molecular weight processing aid that exhibits comparable or enhanced melt flow.

 

Robust Processing
SURECEL™ 488 shows a substantial observed difference in torque, pressure, or melt temperature.
 

Cell Morphology
The ultra-high molecular weight processing aid maintained cell morphology at a lower loading level. Micrographs were prepared from free-foamed PVC rods that were extruded under equivalent conditions.

     _{*Scale indicates 1mm and each division = 100 microns}

Summary
If you are interested in creating more efficiency in your vinyl foam productions, SURECEL™ 488 offers best-in-class fusion, processing, and melt strength.
 

PARALOID and the DOW Diamond are trademarks of The Dow Chemical Company ("Dow") or an affiliated company of Dow.

NOTICE: No freedom from infringement of any patent owned by Dow or others is to be inferred. Because use conditions and applicable laws may differ from one location to another and may change with time, Customer is responsible for determining whether products and the information in this document are appropriate for Customer's use and for ensuring that Customer's workplace and disposal practices are in compliance with applicable laws and other government enactments. The product shown in this literature may not be available for sale and/or available in all geographies where Dow is represented. The claims made may not have been approved for use in all countries. Dow assumes no obligation or liability for the information in this document. References to “Dow” or the “Company” mean the Dow legal entity selling the products to Customer unless otherwise expressly noted. NO WARRANTIES ARE GIVEN; ALL IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE ARE EXPRESSLY EXCLUDED.