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. 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






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






3. Molecule containing a highly reactive unpaired electron






4. Process used to make thermoset fibers by performing the polymerization reacting in a solbent as the material flows through a spinneret and into a quenching bath






5. Specified weight of a polymer that is injected into the mold at the end of the barrel during the injection molding process






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






7. One type of polymer that contains at least 85% of polyacrylonitrile PAN






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






9. Is not asymetric and cannot have multiple configurations






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






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






12. 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






13. Formation of a plymer that occurs when two potentially reactive end groups on a polymer react to form a new covalent bond between the polymer chains. this reaction also forms a biproduct - usually water






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






15. Specific arrangements of atoms that cause organic compounds to behave in predictable ways






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






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






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






19. Plexiglas - lucite - transparent - shatterproof - biocompatible - hockey rinks - taillights - implants






20. Number of bonds a molecule has formed






21. Coloring agents that do not dissolve into the polymer






22. Porcess of breaking large organic hydrocarbons into smaller molecules






23. 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






24. Polymer that is made up a single repeat unit






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






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






27. Orlon - acrilan - lightweight - durable - carbon - fiber precursor - tennis - racing bikes - helmets






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






29. Polymer in which more than 85% of the amide groups are bonded to two aromatic rings






30. Formation of side chains along the backbone; presence of branches disrupts the interactions beween adjacent chains; lowering the tensile strength - melting point - stiffness - crystallinity - and density






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






32. Polymers comprised of two or more different monomers - which attach to the polymer chain in no particular order of pattern






33. Polymers comprised of two or more different monomer units that attach to the chain in an alternating pattern A-B-A-B...






34. Two substituents found at both ends of a polymer chain - which have little to no effect on mechanical properties






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






36. Configuration of a polymer in which the sucstituent is located on opposite sides of the molecule in each repeating unit






37. Conformation in which the largest substituents are offset by 180






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






39. Stiff and extremely inert polymer - low cost - chemical and moisture resistant - outdoor stability






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






41. Term associate with blown - film apparatus - which indicated the point at which the molecules develop a more crystalline orientation around the bubble of air






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






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






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






45. Type of plymer processing similar to extrusion but can be used to develop parts with complex shapes rapidly






46. Part of the extrusion apparatus that hols a large quantity of polymer pellets as they are fed into the barrel






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






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






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






50. Part of the polymer processing apparatus through which the polymer is pushed - causing the polymer to form a simple shape - such as a rod or tube