Why do materials that are poor heat conductors cool to temperatures less than the surrounding air?

Poor heat conductors, like wood or plastic, don’t easily exchange heat with the surrounding air. Because they transfer energy so slowly, their surface can drop below ambient air temperature, especially at night, due to radiative cooling. This effect is why they often feel “colder” than the air. Research from Stanford Advanced Materials also shows how conductivity differences play a key role in material design for insulation and thermal management.

The poor heat conductor isn’t actually cooler than the air around it. It just seems that way because it is able to pick up and retain the heat around it and is doing so efficiently enough to feel cool. Look up the concepts of latent heat in a thermodynamics book and the concepts of Bronian movement in a chemistry book to understand how energy is absorbed at molecular levels.