In polymer materials, lots of parameters affect the properties. All these parameters are explained in Mechanical Base. But there is an another parameter that is common with other materials; Crystallinity. Crystallinity is even valid for polymers. In here, we explain the effect of crystallinity on polymer materials, and the crystallinity phenomenon itself for polymers.
Cristallinity itself is also explained for materials in here.
How Is The Crystallinity For Polymer Materials?
Polymers have lower tencency to ve crystalline structure than other materials. Becuase of this reason, degree of crystallinity of polymers always less than 100%. With the incresing percent of crystallinity in polymer materials, these properties are increased also; heat resistance, stiffness, strength, density.
Polymers can be transparent if they are partially crystalline. This partially crystalline structure depends on glassy(amorphous) structure.
Crystallinity occur folding of linear long-chains of molecules upon themselves in regular basis. For crystalline polymers, there is no situation of 100% crystallinity. There are always non-crystallized long-chains that dispersed around crystallized long-chained molecules in polymers. Lamellar structure occur with that folding phenomenon.
Various polymers have various levels of crystallinity. This level of crystallinity depends on the such parameters;
- Copolymers do not form crystalline structures because of their irregular molecular structure.
- Plasticizers that are promoting to soften polymers, reduces the cristallinity.
- With deformation of thermoplastics in heated situation, increases the crystallinity.
- Like in metals and ceramics, slower cooling rates promote crystalline structure in polymers.
- Linear polymers can make crystal structures.
- Stereoregularity of polymer effects crystallinity; From atactic, syndiotactic to isotactic, the formation of crystalline structures in polymers increases. Atactic polymers generally never form crystalline structures.
Crystallinity of polymers can be summarized like above. Do not forget to leave your comments and questions about crystallinity in polymers below. You precious feedback is very important for us.