材料科学与工程导论
1 Polymerization (聚合作用)is the process by which small molecules (分子) consisting of one unit or a few units are chemically joined to create these giant molecules. Those small molecule units are called _____
A) polymers B) monomers (单体) C) oligomers D)elastomers
cable.
A) For automobile bumper, the best choice of polymer is Natural Rubber.
B) For mineral water bottle, the best choice of polymer is Low-Density (密度) Polyethylene (聚乙烯)
C) For insulating cable, the best choice of polymer is polystyrene (聚苯乙烯).
D) For mineral water bottle^ the best choice of polymer is Polyethylene Terephthalate.
3) In general, for a given type of thermoplastic (热塑性塑胶)the tensile (可延展的) strength, creep resistance impact toughness, wear resistance, and melting temperature all increase with _______
A) degree of polymerization B)density of branching C)tacticity D) crystallinity 4) ABS, composed of acrylonitrile, butadiene, and styrene (苯乙烯)，is one of the most common polymer materials. Styrene and acrylonitrile form a liner copolymer (异量分子聚合物)(SNA) that serves as a matrix. Styrene and butadiene also form a liner copolymer, BS rubber, which acts as the __________ material.D or B? A) fire retardant B) filler C) cross-linking D)plasticizer
5) Epoxies (环氧树月旨)are thermosetting polymers formed from molecules containing a tight C-O-C ring. During polymerization, the C-O-C rings are opened and the bonds are rearranged to join the molecules. If epoxy is used as an adhesive (粘齐ll) for a variety of applications, which kind of adhesives does it belong to? A) Chemically Reactive Adhesives B) Evaporation or Diffusion Adhesives
C) Hot-Melt Adhesives D) Pressure-Sensitive Adhesives
6) What area the major advantages associated with plastic compared to ceramics(陶 瓷)，glasses, and metallic materials?
A) lightweight and corrosion(铁锈,腐蚀卜resistant B) high strength and high-temperature resistant C) high-temperature resistant and insulating D) high stiffness and corrosion-resistant 7) Which one is not a thermoset polymer?
A) Polyethylene B) Natural Rubber C) Epoxy D) Phenolic
8) Depending on the degree of cross-linking, the polyurethanes behave as thermosetting polymers, thermoplastics (热塑性塑胶)，or elastomers. These polymers find application as fibers, coatings, and foams for furniture, mattress, and insulation. Why polyurethanes are versatile(为什么聚氨酯是通用的)？
A) for their polar repeat unit B) for their linear structure
C) for their multi-functional monomer D) for their tactictity structure
9) Liquid Crystalline(透明的)Polymers are polymers which behave as _____ A) liquid B) thermoplastic C) thernoset D) oriented(取向)rods
10) The glass temperature (Tg) is typically about ______ times the absolute melting temperature (Tm).
A) 0.2 to 0.3 B) 0.5 to 0.7 C) 0.8 to 1.0 D) 1.0 to 2.0
11) Most thermoplastic exhibit a non-Newtonian and visicoelastic behavio匸 The stress
and train are not linearly related for most parts of the stress-strain curve. The viscoelastic behavior means when an external (夕卜部的)force is applied to a thermoplastic _ deformation occurs.
B) both elastic and plastic (塑性) A) only elastic
C) only plastic D) neither elastic nor plastic
12) Compare the tensile strength of LDPE, HDPE, PVE, PP, and arrange them in sequence(顺序)from high strength to low tensile strength? A) LOPE>HDPE>PVE>PP B) LDPE>HDPE>PP>PVC C) PVC>PP>HDPE>LDPE D) PVC>HDPE>PP>LDPE
13) Degree of polymerization is usually used to characterize _______ A) cross-linking network B) thermosetting polymer C) polymer degradation D) thermoplastic polymer
14) Silicones(硅)are important elastomer based on chains composed of silicon and oxygen atoms. The silicone rubbers provide high-temperature resistance, permitting use of the elastomer at temperature as high as ____________ °C. Low molecular weight silicones form liquids and are known as silicon oils. A) 100 B) 150 C) 200 D) 300
15) There are a lot of thermoplastic processing methods, typical forming process
includes: extrusion, blow molding, injection molding, thermoforming, calendaring and spinning? If we want to produce sping water bottles, which processing way is best choice?
A) extrusion 挤ill成型 B) blow molding 吹塑成型 C) injection molding 注射成型 D) thermoforming 热成型
16) The recycling of thermoplastics is relatively easy and practiced widely. Many of the everyday plastic products you encounter (bags, soda bottles, yogurt containers, etc.) have numbers stamped on them. For PRT products, the number is 1. For HOPE and LDPE, the numbers are __________ ，respectively. Other plastics are marked number 7,
A) 3 and 4 B) 4 and 5 C) 2 and 4 D) 2 and 3
17) The temperature above which a polymer burns, chars, or decompose. Which team is appropriately used in describing the remperature? A) Tg B)Td C) Tm D) HDT
18) Which forming process is not a best choice for thermosetting polymers. A) Compression molding B)transfer molding C) reaction injection D) spinning
19) Elastomers are thermoplastics or lightly cross-linked thermosets that exhibit
greater than ______ elastic deformation. A) 0.2% B)2% C) 20% D)200°/o
20) Thermoplastic elastomers combine feature of both thermoplastics and elastomers. At high temperature, these polymers behave as __________ and are plastically into shapes, at how temperature, they behave as ________
A) thermoplastics; elastomers B) thermoplastics; thermosetting polymers C) elastomers; thermoplastic D) elastomers; thermosetting polymers
21 Define (a) a thermoplastic, (b) thermosetting plastics, (c) elastomers, and (d) thermoplastic elastomers.
Thermoplastics :热后可塑性物质是由一些单体聚合成长链组成，它们代 表性的特
性是可塑性，延展性。链可能有分枝也可能没有分枝。
Thermosetting :热硬化性的聚合体由强烈地彼此交叉结合形成三度空间的网 络结构的分子的长链(线的或者分枝)组成。
Elastomers :弹性体就是众所周知的橡胶。它们有人于200%的弹性变形。 这些可能是热后可塑性物质或者较弱交叉结合的热固物质。这个高分子链由在受 到一个力之后可逆仲长(收缩)的像卷一样的分子组成。
Thermoplastic elastomers :热塑性的橡胶是一组特殊的高分子。它们具有热 后容易处理的热塑性和弹性。
22) Explain what the following terms mean in polymer materials: decompositions temperate (Td), heat distortion temperature (HDT), glass temperature (Tg), and melting temperature (Tm).
decomposition temperature：分解温度是这种物质在分解成其他物质时的温度 heat distortion temperature：热变形温度是指材料在物理性能和电性能方面发生大 的变化
时的温度
glass temperature:高聚物由高弹态转变为玻璃态的温度 melting temperature：有固体变为液体的温度
23) Topical forming processes for thermoplastic are schematicly shown blew, give each forming process a name and explain what kind of plastic products can be made by corresponding forming process.
挤出吹塑延展喷涂 .............
Extrusion (挤出):
Blow Molding (吹塑)：聚乙烯、聚氯乙烯、聚丙烯、聚苯乙烯、热塑性聚酯、 聚碳酸
酯、聚酰胺、醋酸纤维素和聚缩醛树脂等
Transfer Molding (延展)：聚氯乙烯、纤维素、改性聚苯乙烯等 (喷涂)：聚乙烯、聚氯乙烯、聚酰胺、聚乙烯醇、聚三氟氯乙烯等
24) The molecular weight of polymethyl methacrylate (PMMA) is 250,000g/mol. If all of the polymer chains are the same length?
材料科学与工程导论(双语)复习用.docx
