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华南理工大学材料导论复习资料

Define the following terms.1.Condensation polymerization and Free radical polymerization reaction2.Monomer, Oligomer, the repeating unit3.Alternating copolymer, Block copolymer4.Branched Polymer, syndiotactic polymer, atactic polymer5.Crosslinking, vulcanization6.Chain Transfer, Initiation, Propagation, and Termination7.Thermoset and Thermoplastic8.Glass Transition Temperature9.Plasticizers, Ziegler-Natta catalystspression molding, Extrusion, Injection and Blow moldingMultiple choices.1.Tire cords, the film used as backing for magnetic recording tape in audio and videocassettes, and plastic soft-drink bottles are all composed of what polymers?a. poly(tetrafluoroethylene)b.high-density polyethylenec.nylond.poly(ethylene terephthalate)2.What term is used to indicate a polymerization that occurs without the growth of a chainmonomer by monomer, but instead occurs as monomers form dimers, dimers form tetramers, etc.?a. Non-chainb. Discontinuousc. step-growthd. irregular-increment3.Who developed catalysts that can produce, exclusively, either isotactic or syndiotacticpolymers?a.Carothersb.Ziegler and Nattac.Staudingerd.Goodyear4.Who gave the macromolecular hypothesis?a.Carothersb.Ziegler and Nattac.Staudingerd.Goodyear5.Fabrics or films made of which of the following polymers are most sensitive to damagefrom solutions of strong bases?a. Nylonb. Polyethylenec. poly(vinyl chloride)d. polystyrene6.Who produced billiard balls using collodian as a substitute for ivory?a.Hyattb.Stinec.Goodyeard.Staudinger7.In which polymer is -(-CF2-CF2-)n- the repeating unit?a.Acrilanb.Orlonc.Lucited.Teflon8.The repeat unit in a polymer is called thea. monomerb. oligomerc. degree of polymerizationd. mer9.The smallest repeating unit of a polymer is:a. Polymersb. Monomersc. Oligomersd. dimer10.In a Isotactic polymer,a.the side groups on a polymer chain are all generally on the same side of the polymerchain.b.the side groups of the polymer chain generally alternate their orientation from one sideto the other.c.the side groups of the polymer chain occur randomly on both sides of the polymerchain.d.there are no side groups on the polymer chain.tex is the source of:a.nylon.b.isoprene.c.natural rubber.d.cis-1,4-polybutadiene.12.The type of polymer that is linear and distorts with heat is calleda. cross-linkedb. thermosetc. thermoplasticd. highly branched13.PE polymerization occurs in steps with the following order:a. initiation, activation, propagation, terminationb. activation, initiation, propagation, terminationc. propagation, initiation, activation, terminationd. termination, activation, initiation, propagation14.If A and B represent mers in a polymer, which is the random copolymera. AAAABABBABABBBb. AAABBBAAABBBAAc AABBBBAABBBBAABBBBd. none above15.A blend isa. a physical mixtureb. a compoundc. bound together by primary bonds onlyd. a single phase material16.With increasing concentration of plasticizer the modulus of PVCa. increasesb. decreasesc. stays the samed. none above17.PVC tubing is being used for transporting water. If organic solvents are run through thistubing it becomes stiff and somewhat brittle. This is becausea. The solvent plasticizes the tubing, raising the Tgb. The solvent removes plasticizer, lowering the Tgc. The solvent removes plasticizer, raising the Tgd. The solvent plasticizes the tubing, lowering the Tg18.What are the major advantages of plastics compared to ceramics, glasses and metallic materials?a. Low strength and high-temperature resistantb. Lightweight and corrosion-resistantc. High-temperature resistant and insulatingd. High stiffness and corrosion-resistant19.Consider the properties of the following two polyethylene samples. Sample 1 wasproduced by a high pressure process while sample 2 was synthesized using a catalyst.Polyethylene 1 Polyethylene 2Mol wt. 200,000 200,000Density (g/cm3) 0.92 0.96Crystalline melting pt. 108°C 133°CStiffness (lb/in2x103) 25 125Hardness (Shore D) 45 65Which of the following statements is true?a. Sample 2 is more branched than sample 1b. Sample 1 is more branched than sample 2c. Sample 1 is more atacticd. Sample 1 is more isotactic20.Consider the two transitions from the “solid” to the liquid or rubbery state shown belowon a plot of specific volume vs. temperature;a. The transition X is a Tg while transition Y is a crystalline melting point.b. Y is the Tg while X is the Tm.c. X is the Tm (melting point ) of a semi-crystalline material and Y is the Tm of an almost perfect crystal.d. none above21.What monomers are most commonly used in addition polymerization?a.carboxylic acidsb.estersc.alkenesd.amides22.Linear polymers tend to bea. thermoplasticb. thermoelasticc. thermophillicd. thermoset23.Thermoplastic elastomers combine features of both thermoplastics and elastomers. Athigh temperature, these polymers behave as and are plastically formed into shapes;at low temperature, they behave as .a. Thermoplastics; elastomersb. Thermoplastics; thermosetting polymersc. Elastomers; thermoplasticsd. Elastomers; thermosetting polymers24.PVC is _________ since it is a ________polymera. thermoset, linearb. thermoplastic, linearc. thermoset, crosslinkedd. thermoplastic, crosslinked25.High density polyethylene cooled slowly from 160°C to room temperaturea. Is still amorphous.b. Crystallizes.c. Is a glass.d. Is a mixture where some regions are rubbery and some regions are glassy.26.Atactic polystyrene (Tg ~ 100°C) quenched (i.e., cooled very quickly) from 120°C to roomtemperaturea. Is still amorphous.b. Crystallizes.c. Is a glass.d. Is a rubbery material.27.Vinyl polymers include all of the following excepta. polyethyleneb. polyvinyl chloridec. PMMAd. Polystyrene28.Which of the following materials is copolymer?a. PPb. SBSc. PVCd. PA29.Which of the following polymers would you expect to be most suitable for the productionof a rubber car bumper guard?a. Atactic polystyrene (Tg ~ 100°C)b. A random ethylene/propylene copolymer (50/50 composition) Tg ~ –40°C).c. Low density polyethylene.d. High density polyethylene.30.Which processing way can manufacture film, unlessa. Extrusionb. Injectionc. Blow moldingd. Calendering31.Which pairs of monomers would you use to make a polyester?a.Phenol and formaldehydeb.Styrene and butadienec.Terephthalic acid and ethylene glycold.Ethylene and propylene32.Which of the following polymers is most likely to be optically transparenta. Atactic polystyreneb. Isotactic polystyrenec. Linear Polyethylened. Nylon 6,633.Melt fracture occursa. When chain molecular weight is too highb. When a polymer is extruded too quicklyc. When a polymer is extruded too slowlyd. When a polymer close to its Tg is extruded.34.Consider the stress/strain diagrams shown below. Which of these would most closelycorrespond to the mechanical behavior of Isotactic polypropylene?a. curve Ab. curve Bc. curve Cd. none above35.In commercial practice, poly(ethylene terephthalate), or PET, is manufactured by whatchemical transformation?a. Transesterificationb. reaction of an acyl chloride with a diolc. condensation of a diacid and a diold. copolymerization with a Ziegler-Natta catalyst36.A plasticizer is used to:a. convert a rubber to a glassy plastic.b. convert a thermoplastic to a glass.c. decrease chain-branching during a polymerization.d. soften a commercial plastic.37.Microscopic regions of highly ordered polymer chains, found at low temperatures withinsolid polymers, are called:a. crystallites.b. amorphous regions.c. microsolids.d. microcells.38.Electron Microscopes can NOT yield the following information.a. Morphologyb. Compositionc. Decomposition temperaturesd. Crystallographic Information39.Capillary rheometers are not used to measure:a. Shear viscosityb. Die swellc. crystallinityd. Melt fracture40.Glass transition temperature (Tg) is detectable by a variety of methods, NOT includinga. Thermal-Mechanical Analysis (TMA).b. Differential Scanning Calorimetry (DSC)c. Scanning electron microscopy(SEM)d. Dynamic Mechanical Analysis DMA。

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