To find out what type of plastic it is look on the back. All automotive plastic is marked to help with recycling it.

This should get you started.

https://en.wikipedia.org/wiki/Recycling_codes

When I do plastic repairs I have found SEM has some very good products but even better is their repair guides for bumpers and other automotive plastics. We do have good repair methods now that were not available 10+ years ago. As you know the first step in a proper plastic repair is to identify the material you are working on.

Take a look;

https://www.semproducts.com/training-resources
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