Customisable Non-charging Material for Electrostatic Mitigation in Powder Processing

Fouling is the accumulation of undesired materials on solid surfaces. In powder processing, fouling is a serious and common issue. This is caused by powder adhesion on processing surfaces, leading to clogging and disruption. Most of the time, powder adhesion is due to triboelectric charging. Electrostatically charged powder adheres to surfaces, accumulating and eventually leading to blockage of channels (e.g., transfer pipes, etc.). When fouling occurs, companies are forced to pause production lines for cleaning and unclogging which leads to productivity losses, energy costs, and manpower expenses. In addition, electrostatic fouling issues have been reported from electronic, plastic and pharmaceutical manufacturing industries as well.

This technology is a customisable polymer coating that reduces the amount of static charge generated when a material contacts the coated surface. By reducing the formation of electrostatic charge, adhesion of materials is reduced, and thus the fouling issue is mitigated as well. The technology provider has currently developed prototypes that have helped solve static charge related issues in pharmaceutical, electronics, food and biomedical research industries respectively.

This technology consists of a customisable polymer coating that can be applied to most surfaces, mitigating the formation of static charge on the surface. The two polymers are chosen based on their charging characteristics against the material of interest; one polymer will charge positively while the other will charge negatively. Once blended in a suitable co-solvent and the ratios of each polymer chosen, the solution can be applied to the surface and cured to create a smooth and continuous polymer coating layer.

The coating is robust and has been shown not to shear off easily. In tests, no coating was transferred into a food sample even after three days of continuous movement/contact. While potentially any polymer can be used in the process, the polymers can also be chosen to fit special manufacturing needs, such as food safe polymers for food processing applications. The coating has also been able to withstand standard autoclave conditions (121 C, 15 psi, 60 mins) with minimal loss of functionality.

In food manufacturing, for example, in the 3 in 1 coffee powder manufacturing industry, charged powder tends to stick to the filling hopper, causing fouling problems that affect product fill uniformity. By coating the filling hopper with a non-charging food grade polymer, the charge on the powder is reduced, thus potentially solving the fouling issue and reducing the cost of production.

In electronics manufacturing, chips are transported in a sealed carrier tape/cover tape combo. When the cover tape is removed, the chips tend to stick to the cover tape, causing the chip picker machine to jam. By coating the cover tape with their non-charging polymer, the amount of chips sticking to the cover tape was reduced significantly.

In biomedical research, expensive protein powders often stick to highly charged standard PP laboratory tubes, causing losses during material transfer. By coating the inside of these tubes with their polymer, the amount of powder sticking to the tubes was reduced greatly, thus preventing losses.

In summary, the technology is a polymer coating that can be applied to potentially any surface for any application, depending on the client's needs

Fouling in general remains a severe issue in the food and bioproduct industries with an estimated cost of $7 billion annually. With the use of the non-charging polymer, there would be reduced fouling leading to the decrease in need for maintenance, thus saving costs as well as increasing efficiency of production.

Reduction in fouling leads to:

• Reduced productivity losses when manufacturing processes need to be paused for cleaning/maintenance.
• Improved product uniformity and quality.
• Increased product output.