高分子英语课文翻译.docx
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高分子英语课文翻译.docx
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高分子英语课文翻译
unit1
1.Notallpolymersarebuiltupfrombondingtogetherasinglekindofrepeatingunit.Attheotherextreme,proteinmoleculesarepolyamidesinwhichnaminoaciderepeatunitsarebondedtogether.Althoughwemightstillcallnthedegreeofpolymerizationinthiscase,itislessusefull,sinceanaminoacidunitmightbeanyoneofsome20-oddmoleculesthatarefoundinproteins.Inthiscasethemolecularweightitself,ratherthanthedegreeofthepolymerization,isgenerallyusedtodescribethemolecule.Whentheactualcontentofindividualaminoacidsisknown,itistheirsequencethatisofspecialinteresttobiochemistsandmolecularbiologists.并不是所有的聚合物都是由一个重复单元链接在一起而形成的。
在另一个极端的情形中,蛋白质分子是由n个氨基酸重复单元链接在一起形成的聚酰胺。
尽管在这个例子中,我们也许仍然把n称为聚合度,但是没有意义,因为一个氨基酸单元也许是在蛋白质中找到的20多个分子中的任意一个。
在这种情况下,一般是分子量本身而不是聚合度被用来描述这个分子。
当知道了特定的氨基酸分子的实际含量,它们的序列正是生物化学家和分子生物学家特别感兴趣的地方。
1,题目:
Anotherstriking...答案:
.thatquantitylowsaturationbottommuchabsorb
2.乙烯分子带有一个双键,为一种烯烃,它可以通过连锁聚合大量地制造聚乙烯,目前,聚乙烯已经广泛应用于许多技术领域和人们的日常生活中,成为一种不可缺少的材料。
Ethylenemoleculewithadoublebond,asakindofolefins,itcanmakechainpolymerizationpolyethylene,atpresent,polyethylenehasbeenwidelyusedinmanyfieldsoftechnologyandPeople'sDailylife,becomeakindofindispensablematerials.
Unit3
1Thepolymerizationratemaybeexperimentallyfollowedbymeasuringthechangesinanyofseveralpropertiesofthesystemsuchasdensity,refractiveindex,viscosity,orlightabsorption.Densitymeasurementsareamongthemostaccurateandsensitiveofthetechniques.Thedensityincreasesby20-25percentonpolymerizationformanymonomers.Inactualpracticethevolumeofthepolymerizingsystemismeasuredbycarryingoutthereactioninadilatometer.Thisisspeciallyconstructedvesselwithacapillarytubewhichallowsahighlyaccuratemeasurementofsmallvolumechanges.Itisnotuncommontobeabletodetectafewhundredthsofapercentpolymerizationbythedilatometertechnique.聚合速率在实验上可以通过测定体系的任一性质的变化而确定,如密度、折射率、黏度、或者吸光性能。
密度的测量是这些技术中最准确最敏感的。
对许多单体的聚合来说,密度增加了20%-25%。
在实际操作中,聚合体系的体积是通过在膨胀计中进行反应测定的。
它被专门设计构造了毛细导管,在里面可以对微小体积变化进行高精确度测量。
通过膨胀计技术探测聚合过程中万分之几的变化是很常见的。
Unti4
2合成聚合物在各个领域中起着与日俱增的重要作用,聚合物通常是由单体通过加成聚合与缩合聚合制成的。
就世界上的消耗量而论,聚烯烃和乙烯基聚合物居领先地位,聚乙烯、聚丙烯等属聚烯烃,而聚氯乙烯、聚苯乙烯等则为乙烯基聚合物。
聚合物可广泛地用作塑料、橡胶、纤维、涂料、粘合剂等Thesyntheticpolymersplayanincreasinglyimportantroleonarangeofdomains,whicharesynthesizedbymonomersthroughadditionpolymerizationorcondensationpolymerization.Polyolefinandvinylpolymerhavetakentheleadintermsoftheworldconsumption.PE,PP,etc.belongtothepolyolefin,whilePS,PVCetc.belongtothevinylpolymer.Polymerscanbewidelyappliedinplastics,rubbers,fibers,coatings,gluesandsoon.
Unit7
Ring-openingpolymerizationsproceedonlybyionicmechanisms,thepolymerizationofcyclicethersmainlybycationicmechanisms,andthepolymerizationoflactonesandlactonesbyeitheracationicoranionicmechanism.Importantinitiatorsforcyclicethersandlactonepolymerizationarethosederivedfromaluminumalkylandzincalkyl/watersystems.Itshouldbepointedoutthatsubstitutionnearthereactivegroupofthemonomerisessentialfortheindividualmechanismthatoperateseffectivelyinspecificcases;forexample,epoxidespolymerizereadilywithcationicandanionicinitiators,whilefluorocarbonepoxidespolymerizeexclusivelybyanionicmechanisms.开环聚合反应只能通过离子机理进行,环醚(的开环)聚合主要通过阳离子机理,而内酯和内酰胺的聚合物是通过阳离子或阴离子机理。
对于环醚和内酯型聚合物很重要的引发剂是那些来自于烷基铝和烷基锌/水的体系。
应该指出的是(对于)在活性基团附近有取代的单体,只能由单一机理,(这一机理)是在特定条件下的有效操作,例如环氧聚合能用阳离子和阴离子引发剂,然而碳氟环氧化物的聚合只能是阴离子机理。
Chinese
English
MolecularStructure
聚丁二烯
polybutadiene
聚苯乙烯
Polystyrene
三氯化钛
titaniumtrichloride
四氢呋喃
Tetrahydrofuran
丁基锂
butyllithium
CH3CH2CH2CH2—Li
异丁烯
isobutylene
酚钠
Phenolsodium
氯化钠
sodiumchloride
NaCl
烯丙基
Allyl
CH2=CH—CH2—
光气,碳酰氯
phosgene
Unti8
1Polymerscanbeclassifiedintotwomaingroups,additionpolymersand___condensation__polymers.Thisclassificationisbasedonwhetherornottherepeatingunitofthepolymercontainsthesameatoms__as____themonomer.Therepeatingunitofanadditionpolymerisidentical_with/to____themonomer,whilecondensationpolymerscontain__different/less___becauseofformationof__compound/byproduct___duringthepolymerizationprocess.Thecorrespondingpolymerizationprocessedwouldthenbecalledadditionpolymerizationandcondensationpolymerization.Aswasmentionedearlier,thisclassificationcanresult___in__confusion,sinceithasbeenshowninlateryearsthatmanyimportanttypesofpolymerscanbe_preparedbybothadditionandcondensationprocesses.Forexample,polyesters,polyamidesandpolyurethanesareusuallyconsideredtobe_condensation____polymers,buttheycanbepreparedbyadditionaswellasbycondensationreaction.Similarly,polyethylenenormallyconsideredan_addition_polymer,canalsobepreparedby_condensation_reaction.
2.AnswerthefollowingquestionsinEnglish
(1)Whatischainpolymerization?
Many olefinic and vinyl unsaturated compounds are able to form chain-like macromolecules through elimination of double bond.
(2)Whichkindsofmonomerscancarryoutstep-growthpolymerizationprocess?
Therearetwokindsofmonomerscouldcarryoutstep-growthpolymerizationprocess.Oneis polyfunctional monomersandtheotheris a single monomer containing both types of functionalgroups.
(3)Whatpropertiesofpolymerscanbebasedonformeasuringthemolecularweight?
Themolecularweightofpolymercouldbemeasuredbasedoncolligative properties,light scattering,viscosity,ultracentrifugationsedimentation.
3.Pleasewriteoutatleast10kindsofpolymersbothinEnglishandinChinese
Polyester聚酯
polystyrene,聚苯乙烯
polyamide聚酰胺
polypropylene聚丙稀
polyethylene聚乙烯
polyurethane聚氨酯
polyvinylalcohol
聚乙烯醇
Polyvinylchloride
聚氯乙烯
polybutene聚丁烯
polyether聚醚
(1)Pleasewriteoutatleast10kindsofmonomersbothinEnglishandinChineseandthecorrespongingchemicalstructure
5Ingeneral,head-to-tailadditionisconsideredtobethepredominantmodeofpropagationinallpolymerizations。
However,whenthesubstitutesonthemonomeraresmall(anddonotofferappreciablesterichindrancetotheapproachingradical)ordonothavealargeresonancestabilizingeffect,asinthecaseoffluorineatoms,sizableamountsofhead-to-headpropagationmayoccur.Theeffectofincreasingpolymerizationtemperatureistoincreasetheamountofhead-to-headplacement。
Increasedtemperatureleadstolessselective(morerandom)propagationbuttheeffectisnotlarge.Thus,thehead-to-headcontentinpoly(vinylacetate)onlyincreasesfrom1.30to1.98percentwhenthepolymerizationtemperatureinincreasedfrom30to90℃.
通常在所有聚合物的链增长中,头-尾加成是主要方式。
然而,当单体中的取代基很小(对接近的自由基没有空间阻碍)或没有较大的共振稳定作用,如氟原子,则有相当量的头头增长发生。
提高聚合温度的影响是提高头-头排列的量。
温度的提高导致较少的选择(更多的无规)增长,但影响不大。
因而,在聚乙酸乙烯酯中,当聚合温度由30C提高到90C,头-头含量仅由1.3%提高到1.98%。
2.WriteoutanabstractinEnglishforthetextinthisunit
Polymerswithdifferentstructurespresentvariousproperties.Usually,polymersaredividedintothreecategories,i.e.plastic,elastomer,fiberwithdifferentinitialmodulusrangerespectively.Polymersshowquitedifferentbehaviorsduetothedifferentinterchainforcesinelastomerandfiber.However,withtheadventofnewtechniquesandmechanismstoimprovethestructureofpolymers,polymersmaybeclassifiedandnamedaccordingtothemechanism,andtheirpropertieswilllargelydependonthestructure.
3.PutthefollowingwordsintoChinese
entanglement纠缠irregularity无规sodiumisopropylate异丙醇钠permeability渗透性crystallite微晶stoichiomertricbalance当量平衡fractionation分馏法lightscattering光散射matrix基体diffraction衍射
4.PutthefollowingwordsintoEnglish
形态morphology酯化esterification异氰酸酯isocyanate
杂质impurity二元胺diamine转化率changeratio多分散性polydispersity力学性能mechanicalproperty构象conformation红外光谱法infraredspectroscopy
常见聚合物命名
(1)常见杂链和元素有机聚合物类型
Polyamide----聚酰胺.Polyester----聚酯Poly‘urethane------聚氨酯Polysiloxane-------聚硅氧烷Phenol-formaldehyde----酚醛.Urea-formaldehyde-----脲醛Polyureas------聚脲Polysulfide-----聚硫Polyacetal-------聚缩醛Polysulfone(polysulphone)------聚砜Polyether---------聚醚
第五单元
Traditionalmethodsoflivingpolymerizationarebasedonionic,coordinationorgrouptransfermechanisms.
活性聚合的传统方法是基于离子,配位或基团转移机理。
Ideally,themechanismoflivingpolymerizationinvolvesonlyinitiationandpropagationsteps.
理论上活性聚合的机理只包括引发和增长反应步骤。
Allchainsareinitiatedatthecommencementofpolymerizationandpropagationcontinuesuntilallmonomerisconsumed.
在聚合反应初期所有的链都被引发,然后增长反应继续下去直到所有的单体都被消耗殆尽。
Atypeofnoveltechniquesforlivingpolymerization,knownasliving(possiblyuse“controlled”or“mediated”)radicalpolymerization,isdevelopedrecently.最近开发了一种叫做活性自由基聚合的活性聚合新技术。
ThefirstdemonstrationoflivingradicalpolymerizationandthecurrentdefinitionoftheprocessescanbeattributedtoSzwarc.
第一个活性自由基聚合的证实及目前对这一过程的解释或定义,应该归功于Szwarc。
Uptonow,severallivingradicalpolymerizationprocesses,includingatomtransferradicalpolymerization(ATRP),reversibleaddition-fragmentationchaintransferpolymerization(RAFT),nitroxide-mediatedpolymerization(NMP),etc.,havebeenreportedoneafteranother.
到目前为止,一些活性自由基聚合过程,包括原子转移自由基聚合,可逆加成-断裂链转移聚合,硝基氧介导聚合等聚合过程一个接一个被报道。
Themechanismoflivingradicalpolymerizationisquitedifferentnotonlyfromthatofcommonradicalpolymerizationbutalsofromthatoftraditionallivingpolymerization.
活性自由基聚合的机理不仅完全不同于普通自由基聚合机理,也不同于传统的活性聚合机理。
Itreliesontheintroductionofareagentthatundergoesreversibleterminationwiththepropagatingradicalstherebyconvertingthemtoafollowingdormantform:
活性自由基聚合依赖于向体系中引入一种可以和增长自由基进行可逆终止的试剂,形成休眠种:
Thespecificityinthereversibleinitiation-terminationstepi
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