Ariana's Favorite Things List Edit. Favorite Color(s): Periwinkle blue, marshmallow white, sea foam green, and coral pink. She likes pastel colors. Favorite Food(s): Strawberries and Sushi. Favorite Music: Imogen Heap and Celine Dion. Favorite TV Show: Gossip Girl.
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.
On the other hand, the atoms (ions) in ionic materials show strong attractions to other ions in their vicinity. This generally leads to low melting points for covalent solids, and high melting points for ionic solids. For example, the molecule carbon tetrachloride is a non-polar covalent molecule, CCl 4. It's melting point is -23Â°C. By contrast, the ionic solid NaCl has a melting point of 800Â°C.