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






2. One of the two different types of termination in the polymerization process. during this type of termination - the free radicals from two different polymer chains join to end the propogation process






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






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






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






6. Device used in the processing of polymers that melts polymer pellets and feeds them continuously through a shaping device






7. 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






8. Low- molecular- weight building blocks repeated in the polymer chain






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






10. Coloring agents that do not dissolve into the polymer






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






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






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






14. 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






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






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






17. Is not asymetric and cannot have multiple configurations






18. 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






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






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






21. Porcess of breaking large organic hydrocarbons into smaller molecules






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






23. Relative configuration of adjecent asymmetric carbons






24. Simple polymeric material produced as pellets in large quantities






25. First step in the process of polymerization - during which a free radical is formed






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






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






28. 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






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






30. Polymer that is made up a single repeat unit






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






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






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






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






35. 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






36. 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






37. Softening agents






38. Molecules added to a polymer to enhance or alter specific properties or molecules added to concrete for purposed other than altering a specific property






39. 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






40. Polymers in which one chain of a particular monomer is attached as a side to a chain of another chain of monomer






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






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






43. Molecule containing a highly reactive unpaired electron






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






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






46. Additives whose primary purpose is to reduce the final cost of the product






47. Covalent bonding of the polymer backbone and side groups






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






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






50. Process of pushing polymers through a spinneret and winding the solidified fibers onto a tow - which imposes a shear stress on the fibers upstream as they emerge from the spinneret