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






2. 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






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






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






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






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






7. 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






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






9. Second stage of polymerization process during which the polymer chain begins to go as monomers are added to the chain






10. 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






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






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






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






14. Molecule containing a highly reactive unpaired electron






15. 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






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






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






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






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






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






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






22. 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






23. Atoms attached to the polymer backbone.






24. 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






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






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






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






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






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






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






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






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






33. Additives that cause swelling - which allows the polymer chains to slide past one another more easily - making the polymer softer and more pliable. also used to decrease the viscosity of cement paste to make it easier to flow






34. Is not asymetric and cannot have multiple configurations






35. 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






36. An acid and an alcohol






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






38. 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






39. Covalent bonding of the polymer backbone and side groups






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






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






42. Primary raw material for most polymers






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






44. 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






45. 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






46. Porcess of breaking large organic hydrocarbons into smaller molecules






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






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






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






50. Large spool that is used to wind solidified polymer fibers after they have been pushed through the spinneret