Introduction to Vapor Polishing...
Vapor polishing is a method that is used to “polish” the rough surfaces of machined or molded parts made from some common engineering plastics. Vapor polishing transforms rough, opaque surfaces into shiny, transparent ones without any loss of material. This is particularly useful for medical device components which need to look clean, be clean, and stay clean. Unpolished components look unfinished, and the rough surface of an unpolished component is more difficult to get clean and keep clean. Vapor polishing is also extremely useful for industrial plastic parts which have very strict dimension tolerances or require a clear, clean finish.
HOW IT WORKS
The surface of the part to be polished is exposed to heated solvent vapor. The vapor melts a very thin layer on the surface of the part, and surface tension then “spreads” that melted plastic evenly over the surface resulting in a smooth, clear finish. After polishing is complete, the vapor evaporates off of the part, leaving it free from chemical contamination.
Advantages...
Vapor polishing turns an opaque part into a crystal clear part. It is rapid, clean, and does not measurably distort or change the dimensions of the part. No material is removed during polishing, and no contaminating abrasives or waxes come into contact with the part. The only materials that come into contact with the part are the solvent vapor, which is readily removed, and a specially-designed part holder. This is particularly valuable in Medical Device polishing where contamination could be life threatening.
The vapor also flows into very small crevices, holes, and even screw threads, thus polishing those surfaces which would be either impossible or very difficult and expensive to polish by other means.
Risks...
As long as the people conducting the procedure are experienced in chemical vapor and plastic-part handling, vapor polishing has few risks, especially when compared to traditional polishing methods. The biggest practical risk to the part stems from polishing a part which has not been properly cleaned of debris and residue. In this case, the melting-and-smoothing process which occurs on the surface of the part will, in effect, weld such contaminants into the surface. Other risks include crazing with some materials, and distortion or tide marks if the polishing is too prolonged. Again, experienced operators can avoid or minimize these risks.
Experience...
Aspire Biotech, Inc. personnel have extensive biomaterials expertise – one of the most exacting fields of materials science. Our search for excellence in this field encompasses biomaterial synthesis, fabrication, and medical-device design; and that journey has led to our expert refinement of the vapor polishing process over time.
In just the last three years, Aspire has polished over 30,000 Medical Device components of different shapes, sizes, and materials. We have experience polishing acrylics, polycarbonates, polysulfones, and other proprietary materials. Our team has developed unique and specific polishing protocols, ensuring that optimal results are achieved for each material and part type we encounter. Medical device vapor polishing presents the most difficult challenges and rigid performance requirements in the field. If we can satisfy the Medical Device industry, we can meet and exceed your expectations.
Medical Device Components...
Vapor polishing is a rapid, inexpensive way of improving the look and functionality of your medical device components while maintaining strict tolerances and avoiding contamination. Plastic medical-device components that are machined or molded often have opaque, scratched, or marred surfaces. Vapor polishing is an exceptionally good method of creating a crystal-clear surface to the part that demonstrates its cleanliness and purity. No material is removed or lost from the component during polishing, so even the strictest of tolerances can be maintained. Because only vapor, which evaporates, and a specially-designed part holder ever touch your component, contamination concerns are reduced dramatically as compared to other polishing methods.
Industrial Components ...
Vapor polishing will significantly improve the aesthetics of your critical parts and can also improve functionality, especially if optical clarity is desired. Machined or molded parts constructed of clear acrylic, polycarbonate, polysulfone, polyethersulfone, polyethylene imine, acrylonitrile butadiene styrene, cellulose acetate butyrate, and some other specialty polymers may be effectively vapor polished to a high gloss or optical transparency.
Aspire Biotech, Inc. will be delighted to work with you to determine if your material is suitable for vapor polishing. As necessary, we are prepared to develop special tools and polishing protocols designed to ensure the best results at the lowest cost and fastest turn-around times.
Q. Will vapor polishing remove all tool marks from my parts?
A. No. Deep tool marks will be made less apparent but will not be removed entirely. Only the surface is polished, so “steps” and excess materials are not removed.
Q. Why won’t vapor polishing work on all types of materials?
A. Vapor polishing will only work on materials which can be readily dissolved in a low-boiling solvent that can “kiss” the surface and then evaporate rapidly. Insoluble polymers, high molecular weight grades of polymers, thermosetting resins, and cross-linked polymers may not be suitable for vapor polishing.
Q. If the part is going to be polished, why do I have to clean it first?
A. Vapor polishing does not clean the surface and does not remove anything from the surface. It can only smooth the surface. Dirt, debris, and residue on the surface of the part become much more noticeable after polishing. Hence, parts must be thoroughly cleaned before being polished. Aspire has extensive experience cleaning plastic parts and we would be happy to help develop a cleaning protocol, or even perform the pre-polish cleaning for you as we have done for other customers.
Q. I’ve heard that solvent vapors can be toxic. Is there a chance that my parts could be toxic when they return?
A. Not with Aspire Biotech, Inc. The solvents we use for vapor polishing are carefully selected to evaporate rapidly. Our degassing cycle further ensures that there are no detectable fumes.
Q. Will polishing change the dimensions of my part or the accuracy of the machining?
A. Because vapor polishing works only on the very surface layer of your part and does not add or remove material, it cannot change the dimensions. We have experience polishing parts with very fine features and extremely tight dimension tolerances with no apparent loss of machined accuracy.
