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2. Crystallization of polymers - Wikipedia

   en.wikipedia.org/wiki/Crystallization_of_polymers

   Drawn semi-crystalline polymers are the strongest polymeric materials due to the stress-induced ordering of the molecular chains. [27] Other defects, such as voids, occur in the semi-crystalline polymer under tensile stress and can drive the formation of the neck. The voids can be observed via small angle x-ray scattering.

3. Plastic - Wikipedia

   en.wikipedia.org/wiki/Plastic

   Many plastics are completely amorphous (without a highly ordered molecular structure), [22] including thermosets, polystyrene, and methyl methacrylate (PMMA). Crystalline plastics exhibit a pattern of more regularly spaced atoms, such as high-density polyethylene (HDPE), polybutylene terephthalate (PBT), and polyether ether ketone (PEEK ...

4. Polyethylene terephthalate - Wikipedia

   en.wikipedia.org/wiki/Polyethylene_terephthalate

   Depending on its processing and thermal history, polyethylene terephthalate may exist both as an amorphous (transparent) and as a semi-crystalline polymer. The semicrystalline material might appear transparent (particle size less than 500 nm ) or opaque and white (particle size up to a few micrometers ) depending on its crystal structure and ...

5. Thermoplastic - Wikipedia

   en.wikipedia.org/wiki/Thermoplastic

   Amorphous and semi-amorphous plastics are less resistant to chemical attack and environmental stress cracking because they lack a crystalline structure. Brittleness can be decreased with the addition of plasticizers , which increases the mobility of amorphous chain segments to effectively lower the glass transition temperature.

6. High-performance plastics - Wikipedia

   en.wikipedia.org/wiki/High-performance_plastics

   There are many synonyms for the term high-performance plastics, such as: high temperature plastics, high-performance polymers, high performance thermoplastics or high-tech plastics. The name high temperature plastics is in use due to their continuous service temperature (CST), which is always higher than 150 °C by definition (although this is ...

7. Polycarbonate - Wikipedia

   en.wikipedia.org/wiki/Polycarbonate

   Thermally processed material is usually totally amorphous, [7] and as a result is highly transparent to visible light, with better light transmission than many kinds of glass. Polycarbonate has a glass transition temperature of about 147 °C (297 °F), [8] so it softens gradually above this point and flows above about 155 °C (311 °F). [9]

8. Shape-memory polymer - Wikipedia

   en.wikipedia.org/wiki/Shape-memory_polymer

   In the amorphous state, polymer chains assume a completely random distribution within the matrix. W represents the probability of a strongly coiled conformation, which is the conformation with maximum entropy, and is the most likely state for an amorphous linear polymer chain.

9. Polypropylene - Wikipedia

   en.wikipedia.org/wiki/Polypropylene

   With speed welding, the plastic welder, similar to a soldering iron in appearance and wattage, is fitted with a feed tube for the plastic weld rod. The speed tip heats the rod and the substrate, while at the same time it presses the molten weld rod into position. A bead of softened plastic is laid into the joint and the parts and weld rod fuse.