Can anyone tell me is there any main difference between molding of medical plastics and other conventional plastics what parameters should be consider while processing medical plastics

Hi, Khalid,
if you can tell me which kind of plastics do you apply in medical industry, maybe i can tell you the detail difference.

As with any plastic, check the data sheets but from a medical point of view, like materials medical spec to none medical should have little differences. Coming from a custom molder turned medical manufacturer we had little difficulty with the change of process. We ran PVC/PC and Radiation Stable PC/PP/Nylon.

Cleanliness is a must, avoidance of grease/oil on parts we had a clean-room designed that cost very little, but passed all certifications! Also material tracability & C of C's are important to most medical device manufacurers.

HI Khalid,
The actual molding process is not different between medical and non medical molding of the same material. The differences arise in material selection, how it is handled in terms of traceability, and how the parts are handled after the molding is complete.
Tom

I totally agree with Mr. Graham and Guetterman.
You may also have to do more work on the processing side for documentation.
You may be required to perform a DOE or Validation studies of you processes and document that for medical projects. Those items can be used for non-medical but may not be required.

Medical molding is typically closer tolerance than most molding. Also the usage of mold releases is not tolerated. Cleanliness is absolute.

It all depends on the parts, as to tolerances and cleanliness the main thing in medical moulding is to follow the spec to the letter and make sure you have full traceability of materials used! And in most of the parts I have made, Virgin material is a must!

Khalid,

Just reiterating the previous responses - The actual molding is the same, the only difference is the environment and tracking/documentation of the process.

I agree with Darren but would have to say with most medical jobs the pre-molded set up work and the customer’s requirements are what can be the main difference, I run some jobs that require us to not only run in a clean room but we are required to pull the screw / barrel off the press and remove them from the clean room to be cleaned each time we run. Others require us to dry the material in vacuum ovens with Nitrogen.
We should also talk about the customer’s requirements and validating the Medical Molding Process, this is required by most Medical Customers, Installation Qualification (IQ), Operation Qualification (OQ), and Performance Qualification. This can be a relatively simple process or a more complicated process depending on the customer and the product.
I recently attended a seminar about this subject (Validating Medical Molding Processes & parts) the instructor was John Bozzelli, I would recommend educating yourself on this and John’s seminar would be a great place to start.
As with any molded product we molders and have a moral and yes legal obligation to insure we continue to do everything we can to insure the parts we design, tools we build, and parts we mold meet or exceed not only our customers’ requirements but our requirements as well.