We are needing a waterproof enclosure for our hardware. What recycled companies have you had good/bad experiences with? Any particular plastics that were better? Any other good info?
I work for a Injection Molding company. Injection molded grades of plastic will behave differently than Blow Molding Grades, sheet plastic or extruded grades.
I could write an encyclopedia here on this subject as it is very complicated and there are a lot of different types of plastics and grades of each one of them.
As far as Injection molded plastics goes, the easiest to recycle are also (luckily) the most common. Polyethylene (HDPE, PE, LDPE), Polypropylene (PP, homo or copolymers) ABS, Poly-carbonate (PC), PVC and Nylon.
All of these materials will lose strength and other properties when recycled. It is always recommended to mix virgin material with the recycled material (known as regrind). What percentage would depend on the material and the molded part.
For HDPE and PP you could use up to 70% regrind, depending on the barrel size of the machine. Virgin material is in round pellets but regrind will have rough edges and won't flow down the hopper as easily.
ABS and PC can be mixed together in many cases and can be used in mixes up to 50% without any major property loss.
Nylon 10%-20% but it is hydroscopic so it will absorb or lose moisture when recycled. This will change it's flexibility and strength. This may be remedied by adding an impact modifying additive or glass.
As far as recycling companies go, there are a lot and I can't just recommend one. The key will not be so much the recycling company but the source of the material that that company has.
- How consistent is the material type? Is it mixed with other material types, colors or grades (e.g. melt flow).
- How consistently clean is the material? You would be surprised to know that it is very common to find metal and paper in recycled plastics which is a major headache for molders.
As far as a waterproof enclosure goes. You could easily use recycled material in large quantities, no problem. Just don't use recycled seals! :D Hehehe...
I hope this helps! I apologize for the delay in answering. There are very few plastics questions here on Clarity!
Feel free to contact me or schedule a call if you have any more questions and I would be glad to help with material selection!