Test your basic knowledge |

Modern Material Science And Engineering 2

Subject : engineering
Instructions:
  • Answer 50 questions in 15 minutes.
  • If you are not ready to take this test, you can study here.
  • Match each statement with the correct term.
  • Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.
1. Atoms attached to the polymer backbone.






2. One method of expressing the molecular weight of sample of polymers with averaging based on weight; this method is more useful when large molecules in the sample dominate the behavior






3. Small chains of bonded monomers whose properties would be altered by the addition of one more monomer unit






4. Polymers with low melting poins due to the lack of covalent bonding between adjacent chains. such polymers can be repeatedly melted and re- formed






5. Polymers that can stretch by 200% or more and still return to their original length when released; polyurethatnes and the aliphatic thermosets(rubbers)






6. Lightwieght polymer that absorbs water well; the first syntheric polymer ever constructed






7. Additives that improve a polymer's resistance to variable that cause bonds to rupture - such as heat and light






8. Second- order thermodynamic transition in which the onset of large scale chain mobility occures in polymers. Bellow Tg the polymer is glasslike and brittle. above Tg the polymer becomes rubbery and flexible






9. Pigments or dyes that change the way light is absorbed or reflected by a polymer






10. Term used to describe a polymer that contains significant numbers of both syndiotactic and isotactic dyads






11. Occurs when substituent are directly aligned - causing substantial repulsion between the substituents and an unfavorable conformation.






12. On of the two most common reaction schemes used to create polymers - involving three steps: initiaition - propogation - and termination






13. Coloring agent that is dissolved directly into the polymer - causing the polymer to change color






14. Long chain polymers that contain at least 85% of an ester of a substituted aromatic carboxylic acid. these fibers are strong and can dyed or made transpared






15. Circular - stationary block with small holes through which molten polymer can flow to take the shape of a fiber






16. Polymers comprised of two or more different monomers that attach to the chain in long runs of one type of monomer - followed by another monomer AAAAAAAAAAAAABBBBBBBBBBBBBBBBBBAAAAAAAA






17. Polymers that cannot be repeatedly melted and re- formed due to strong covalent bonding between chains






18. Last step in the polymerization process - which occurs when the free radical of a polymer chain joins the free radical on an end group






19. Polymers that contain amide (- N-) groups in the chain






20. Polymer that is made up a single repeat unit






21. Number of repeat/structural units in a polymer chain






22. Peice of the extrusion apparatus that is used as a filter to separate unmelted particles - dirt - and other solid contaminants from the molten polymer






23. Simple polymeric material produced as pellets in large quantities






24. Configuration of a substituent in a polymer - in which the substituent is located on the same side of the polymer chain in all repeating units






25. Process by which chemical cross - linkages can form between adjacent polymer chains - strengthening the material without significantly damaging its elastic properties






26. Type of polyamide in which less that 85% of the amide groups are bonded to the aromatic rings






27. High distance- dependent bonding between adjacent polymer chains; usually includes hydrogen bonding - dipoles - and van der waals






28. Smallest repeating unit in a polymer. aka repeat unit






29. Arrangement of the largest substituents where the substituets are offset by 120






30. Covalently bonded atoms which are usualy carbon - that comprise the center of the polymer chain.






31. Technique used to make rayon - which involves treating cellulose from wood or cotton with alkali and extruding it through a spinneret






32. Two or more polymers mechanically mixed together but without covalent bonding between them






33. Covalently bonded chains of molecules with small monomer units repeated from end to end






34. Sylon - transparent - shatter proof - biocompatible - hockey rinks - taillights - implants






35. An acid and an alcohol






36. Relative configuration of adjecent asymmetric carbons






37. Spatial arrangement of substituents around the main chain carbon atom that can be altered only by the breaking of bonds






38. Coloring agents that do not dissolve into the polymer






39. Softening agents






40. Carbon atom capable of multiple configurations due to four different substituents






41. Covalent bonding of the polymer backbone and side groups






42. Formation of a polymer that occurs when two potentially reactive end groups on a polymer react to form a new covalent bond between the polymer chain. this reaction also forms a byproduct - which is typically water






43. All issues related to bonding in polymers including primary and secondary bonding - branching - formations of networks - and end groups






44. Final step in the polymerization process - which causes the elongation of the polymer chain to come to an end






45. Broad category of polymers that includes polymers containing urethane linkages






46. Form of the molecular weight of a sample of polymer chains determined by dividing the mass of the specimen by total number of mols present; always less than weight average molecular weight; all molecules regardless of size correlate well with Mn






47. Part of the extrusion apparatus that contains a heated screw which is used to melt the polymer and the polymer forward into the next chamber






48. Kevlar - Twaron - high tensile strength - lightweight - susceptible to uv degradation - nonconductive - bullet- resistant armor - sports equipment - fire resistance






49. Term used to represent the average molecular weight of a sample containing a wide range of polymer chain lengths. this term is used to avoid confusion between the number average and the weight molecular average weight






50. Conformation that occurs when the largest substituent in a molecule are offset by 60