High-performance plastics don’t play a major role in my blog, but it is good to know that such materials exist and what they can be used for.
The most common amorphous transparent high-performance plastics belong to the polysulfone family, including PSU, PPSU, PES. They are clear, but might be slightly brownish.
Polysulfones are not as resistant to chemicals as semi-crystalline high-performance plastics. In most cases, however, they clearly outperform the common transparent engineering plastics, such as MABS, PMMA or even PC.
Some members of the fluoroplastic family, such as FPA and FEP, can be injection-molded and are transparent although semi-crystalline, but their high price limits their use.
If you need resistance to heat but not necessarily chemicals or hot water, you might see if HT-PC or PMMI meet your needs.
If your component requires mechanical performance, please consider the common weaknesses of amorphous plastics. They are not well-suited for machine design purposes.