rigorous (Adjective). Manifesting, exercising, or favoring rigour; allowing no abatement or mitigation; scrupulously accurate; exact; strict; severe; relentless; as, a rigorous officer of justice; a rigorous execution of law; a rigorous definition or demonstration. rigorous (Adjective). Severe; intense; inclement; as, a rigorous winter.
Polylactic acid or polylactide (PLA, Poly) is a biodegradable thermoplastic aliphatic polyester derived from renewable resources, such as corn starch (in the United States and Canada), tapioca roots, chips or starch (mostly in Asia), or sugarcane (in the rest of the world).eing able to degrade into innocuous lactic acid, PLA is used as medical implants in the form of anchors, screws, plates, pins, rods, and as a mesh. Depending on the exact type used, it breaks down inside the body within 6 months to 2 years.
It is one of the two most common filaments, along with ABS, purchased for use in 3D printers in many western countries. PLA is harder than ABS, melts at a lower temperature (around 180Â°C to 220Â°C), and has a glass transition temperature between 60-65 Â°C, so is potentially a very useful material. It does exhibit higher friction than ABS however which can make it difficult to extrude and more susceptible to extruder jams.