PDA

View Full Version : Plastics



mochinist
10-22-2003, 02:34 AM
Hi people I was wondering if any of you have had much experience working with polypropelene plastic(hope i spelled it right), mainly the gluing of it. I do alot of jobs for one of my customers out of .500 inch poly pro and everything looks great till it comes time to glue. I have tried the glues made specifically for the stuff in two different consistency's ,one is like water and the other like a real sicky stringy gel. I see boxes and display cases made out of this plastic and the glue jobs look beautiful but have not been able to find out how they do it. If any body here has experience with this plastic or knows of a website or book I could check out , that would be great. Thx Alot

Alistair Hosie
10-22-2003, 05:00 AM
You really have to phone a plastic specialist for this info. Don't simply rely on the advice from your general supply store as they will sell you the first thing without really knowing what they are doing.I went to a specialist shop for plastic sheeting they had many types in and just as many adhesives there are so many mew products coming out faster than the general storeman can keep up with and if you want a first class job make sure you ask the right people Alistair

darryl
10-22-2003, 05:11 AM
I wonder if you're not seeing lexan or plexiglass cases, not polypropylene. Lexan is glued with methylene chloride, a very thin chemical, which is wicked into close tolerance joints, actually welding the material. Plexiglass likewise. Other plastics are generally welded with hot air and appropriate plastic welding sticks. I have tried some of the 'over the counter' glues, and found them to be less than ideal. Methylene chloride is a hazardous chemical, avoid breathing the vapors, and when using it, it evaporates quickly, so must be wicked into the joints quickly.

JCHannum
10-22-2003, 08:48 AM
There may be some LocTite or Permatex products that will work. It seems I remember gluing surgical tubing to polypropylene at one time. I don't know about to itself.
For the most part polypropylene is not glueable. Most joints are either hot air welded or ultrasonic welded.

Alistair Hosie
10-22-2003, 10:28 AM
I find the difficulty with plastics is to make a clean joint without too much overspill fogging the surrounding material. This is off putting to look at.
Exactly why the correct glue should be used as it will be clear or whatever colour the plastic is and will be unoticeable Alistair

Brian Gale
10-22-2003, 10:42 AM
Polypro is darned near impossible to glue as it is so inert. That is why it is used for a variety of chemical tanks and containers...because almost nothing sticks to it. A number of polypro components are either spin, sonic, or laser welded (all requiring tooling to do so.) You will need to go to a specialty industrial supplier like Vantico (www.vantico.com) to find any *real* glue solutions if they exist.

Good luck

Evan
10-22-2003, 01:28 PM
See this for gluing polypro

http://www.permatex.com/products/industrial_individual_products.asp?category=adhesi ves&product=Permatex,%20Plastic%20Bonder