高分子化學(xué)總復(fù)習(xí)ppt課件

1、Polymer ChemistryReviewShuizhu Wu2019.11.25 答疑安排： 趙建青 25-101 吳水珠 25-514 劉述梅25-317、25-504 劉海敏 13-204 張安強(qiáng)25-530 12月3日 上午9:00 11:30 下午3:00 5:00(部分) 題型 名詞解釋 10分 5小題 填空 12分 6小題 選擇題 18分 6小題 問答題 35分 7小題 計(jì)算題 25分 5小題Chapter 1 Introduction Basic concepts DP聚合度）聚合度）: 聚合物的結(jié)構(gòu)單元數(shù)或重復(fù)單元聚合物的結(jié)構(gòu)單元數(shù)或重復(fù)單元數(shù)）。數(shù)）。Chain seg

2、ment鏈節(jié)）：結(jié)構(gòu)單元俗稱為鏈節(jié)。鏈節(jié)）：結(jié)構(gòu)單元俗稱為鏈節(jié)。 homopolymer(均聚物均聚物)：由一種單體進(jìn)行聚合所得：由一種單體進(jìn)行聚合所得的聚合物。的聚合物。 copolymer(共聚物共聚物)：由兩種或多種單體同時(shí)參與聚：由兩種或多種單體同時(shí)參與聚合所得的聚合物。合所得的聚合物。 thermoplastic polymer(熱塑性聚合物熱塑性聚合物)：熱塑性是指：熱塑性是指一般線型或支鏈型聚合物具有可反復(fù)加熱軟化或熔化而一般線型或支鏈型聚合物具有可反復(fù)加熱軟化或熔化而再成型的性質(zhì)，具備熱塑性的聚合物稱作熱塑性聚合物。再成型的性質(zhì)，具備熱塑性的聚合物稱作熱塑性聚合物。 therm

3、osetting polymer (熱固性聚合物熱固性聚合物)：熱固性是：熱固性是指交聯(lián)聚合物一次成型后，加熱不能再軟化或熔化而重指交聯(lián)聚合物一次成型后，加熱不能再軟化或熔化而重新成型的性質(zhì)，具有這種性質(zhì)的聚合物稱作熱固性聚合新成型的性質(zhì)，具有這種性質(zhì)的聚合物稱作熱固性聚合物。物。 kinetic chain length(動(dòng)力學(xué)鏈長(zhǎng)動(dòng)力學(xué)鏈長(zhǎng))：動(dòng)力學(xué)鏈長(zhǎng)是指：動(dòng)力學(xué)鏈長(zhǎng)是指每個(gè)活性中心自引發(fā)至終止平均所消耗的單體分子數(shù)每個(gè)活性中心自引發(fā)至終止平均所消耗的單體分子數(shù) 2. Classification and nomenclature of polymers聚合物的分類和命名）3. Poly

4、merization4. Molecular weight and its distribution5. Microstructure6. Linear, branched and crosslinked polymers7. Aggregate structure8. Mechanical properties.Key points:Whats the difference between macromolecule and low-molecular-weight compounds?high molecular weight, repeat unit 分子量大，由分子量大，由許多相同的結(jié)

5、構(gòu)單元經(jīng)共價(jià)鍵重復(fù)連接而成許多相同的結(jié)構(gòu)單元經(jīng)共價(jià)鍵重復(fù)連接而成molecular weight polydispersity and structure polydispersity分子量多分散性和結(jié)構(gòu)多分散性分子量多分散性和結(jié)構(gòu)多分散性Different units 有幾種運(yùn)動(dòng)單元有幾種運(yùn)動(dòng)單元microstructure 結(jié)構(gòu)復(fù)雜，有一次、二次和三次結(jié)結(jié)構(gòu)復(fù)雜，有一次、二次和三次結(jié)構(gòu)。一次結(jié)構(gòu)是指大分子鏈中的結(jié)構(gòu)單元或相構(gòu)。一次結(jié)構(gòu)是指大分子鏈中的結(jié)構(gòu)單元或相鄰結(jié)構(gòu)單元的立體排布。二次結(jié)構(gòu)是指單個(gè)分鄰結(jié)構(gòu)單元的立體排布。二次結(jié)構(gòu)是指單個(gè)分子鏈的構(gòu)象或聚集態(tài)類型。三次結(jié)構(gòu)是指高分子鏈的構(gòu)象

6、或聚集態(tài)類型。三次結(jié)構(gòu)是指高分子聚集體中大分子鏈的排列情況。子聚集體中大分子鏈的排列情況。Whats the difference between thermoplastic resin and thermoset? Thermoplastic: Becoming soft when heated and hard when cooled 聚合物具有的可反復(fù)加熱軟化或熔化而再成型的性質(zhì)Thermoset: A thermoset material cannot be melted and re-shaped after it is cured 交聯(lián)聚合物一次成型后，加熱不能再軟化或熔化而重新成

7、型的性質(zhì)How to distinguish rubber, fiber and plastic? 橡膠分子的柔性大，分子間作用力??；纖維常為結(jié)晶性聚合物，分子間作用力大；塑料的分子間作用力介于二者之間。 分子量的計(jì)算2(/)iiiniiiiiiiiwiiin MmmMnnmMm Mn MMmn M其中ni, mi, Mi分別代表i-聚體的分子數(shù)、質(zhì)量和分子量。MiDPMruChapter 2 Free radical polymerizationMonomers suitable for radical polymerization most of the vinyl monomers ar

8、e suitable except for 1,1-dicyanoethylene nitroethylene2. Mechanism of radical polymerizationInitiation 鏈引發(fā)Propagation 鏈增長(zhǎng)Termination 鏈終止 chain transfer鏈轉(zhuǎn)移 Characteristics of free radical polymerization:Sequence of events: initiation, propagation, termination, chain transfer 基元反應(yīng)：鏈引發(fā)、鏈增長(zhǎng)、鏈終止、鏈轉(zhuǎn)移As t

9、he reaction time is increased, DP (or molecular weight) varies little. 隨反應(yīng)時(shí)間的延長(zhǎng)，分子量聚合度不變The conversion increases as the reaction time is increased. 隨反應(yīng)時(shí)間的延長(zhǎng)，單體濃度逐漸降低，聚合物濃度增加，轉(zhuǎn)化率提高。Small amount of retardant can terminate the polymerization 少量阻聚劑可使聚合終止3. InitiatorsAzo type 脂肪族偶氮化合物 AIBNb. Peroxide 過氧化

10、物 BPOc. Redox systems 氧化還原體系t1/2 = ln2/kd=0.693/kd比較自由基聚合、陽離子聚合、陰離子聚合Ziegler-Natta聚合所用的引發(fā)劑的區(qū)別。自由基聚合：易分解形成自由基的化合物陽離子聚合：一般為L(zhǎng)ewis酸類化合物陰離子聚合：一般為L(zhǎng)ewis堿類化合物Ziegler-Natta聚合：主引發(fā)劑為L(zhǎng)ewis酸類化合物，共引發(fā)劑為L(zhǎng)ewis堿類化合物，但它不是陽離子聚合和陰離子聚合引發(fā)劑的簡(jiǎn)單加合。Rate of initiation: Ri=kdIInitiator efficiency f: the fraction of radicals for

11、med in the primary step of initiator decomposition which are successful in initiating polymerization. 引發(fā)聚合部分的引發(fā)劑占引發(fā)劑分解或消耗總量的分率 Initiator efficiency The induced decomposition of initiator 引發(fā)劑的誘導(dǎo)分解，徒然消耗引發(fā)劑，降低引發(fā)劑效率 The presence of solvent (or monomer) cage which traps the radicals for some period befor

12、e they diffuse apart 籠蔽效應(yīng) and other side reactions 其他副反應(yīng)4. Kinetics of free radical polymerizationThree assumptions: A. KP and Kt are independent of the size of the radical, namely equivalence of reactivity for propagating chain radicals 等活性假定，鏈自由基的活性與鏈長(zhǎng)無關(guān) B. Steady-state assumption: the concentrati

13、on of radicals increases initially, but almost instantaneously reaches a constant, steady-state value. Ri=Rt 穩(wěn)態(tài)假設(shè) C. high DP, the amount of monomers used for initiation is far less than that for propagation, Ri RP 聚合度很大Polymerization rate expression:Autoacceleration: As the polymerization proceeds t

14、he viscosity of the system increases and termination becomes increasingly slower. High viscosity affects termination much more than propagation. Therefore, the quantity kP/kt1/2 increases, the result is an increase in RP and molecular weight.自動(dòng)加速效應(yīng)的本質(zhì)：雙基終止 DP and molecular weight the average number

15、of monomer molecules consumed (polymerized) per each radical which initiates a polymerization chain. 每個(gè)活性種從引發(fā)階段到終止階段所消耗的單體分子數(shù)。 1/DP = 1/DP0 + CTT/M 1/Xn= 1/Xn0 + CTT/M (存在鏈轉(zhuǎn)移反應(yīng)） Chain transfer reactions Vinyl chloride DP depends on T 通用聚氯乙烯的聚合度一般僅由溫度來控制，聚合速率或時(shí)間則由引發(fā)劑濃度來調(diào)節(jié)。 Inhibition and retardation

16、Inhibitors stop every radical and polymerization is completely halted until they are consumed.阻聚使反應(yīng)停止 Retarders are less efficient and stop only a portion of the radicals. 緩聚使反應(yīng)速率減小5. Thermodynamics Equilibrium monomer concentration The ceiling temperature at which the propagation and depropagation

17、rates are equal.Upper temperature limit above which polymer cannot be obtained even from pure monomer.The ceiling temperature ( 當(dāng)Me=1 M時(shí)，聚合和解聚處于平衡狀態(tài)的平衡溫度)聚合上限溫度Chapter 3 Chain copolymerization Types of copolymers: Statistical (Random) 無規(guī)Block 嵌段Graft 接枝Alternating 交替2. Copolymerization equationReact

18、ivity ratios 競(jìng)聚率是均聚增長(zhǎng)和共聚增長(zhǎng)的速率常數(shù)的比值 Copolymer equation3. Types of copolymerization behavior以下各競(jìng)聚率的含義是什么？r1 = 0 自由基1不能與同種單體均聚，只能共聚 r1 = 1 自由基1加成同種或異種單體的難易程度相同，均聚和共聚的高鋁相同r1 1 自由基1容易進(jìn)行均聚r1 = 自由基1不能共聚，只能均聚 ideal copolymerization r1r2=1 r1r2=1， 共聚物組成與單體組成相等 Alternating copolymerization: r1=r2=0 r11, r21 a

19、nd r1r21 non-ideal non-azeotropic copolymerization r11, r21, r21)4. Reactivities of monomer and radical 會(huì)利用競(jìng)聚率判斷單體、自由基的相對(duì)活性注意同一參照物） r1=0.3, r2=1.5: 活性M1 M25. Effects of substituents on the reactivities of monomer and radicalResonance effectThe order of monomer reactivities corresponds to the order o

20、f increased resonance stabilization by the particular substituent of the radical formed from the monomer. The order of substituents in enhancing radical reactivity is the opposite of their order in enhancing monomer reactivity. Polar effects Resonance effects polar effects 取代基對(duì)自由基活性的影響比對(duì)單體活性的影響要大得多。

21、6. Q-e scheme Q describes the resonance factor e describes the polar factor(吸電子基團(tuán)，正值）Ideal copolymerization occurs between two monomers having similar Q and e values, for example, styrene-1,3-butadiene, vinyl chloride-vinyl acetate, and acrylonitrile-methyl acrylate.The tendency toward alternation i

22、s greatest for monomers having similar Q values with high e values of opposite sign, e.g. styrene and maleic anhydride Chapter 4 Polymerization ProcessesComparison of four polymerization methodsAside from the physical difference between the emulsion and other polymerization processes, there is one v

23、ery significant kinetic difference:both high molecular weights and high reaction rates can be simultaneously attained 本體聚合：定義，特征 溶液聚合：定義，特征 懸浮聚合：定義，特征 乳液聚合：定義，特征 乳液聚合的組成，規(guī)律？Chapter 5 Ionic polymerizationCationic polymerization is limited to those monomers with electron-releasing substituents such as

24、 alkoxy, phenyl, vinyl and 1,1-dialkyl for example, butylene, alkoxy alkene, conjugated alkeneAnionic polymerization takes place with monomers possessing electro-withdrawing groups such as nitrile, carboxyl, phenyl, and vinyl 共軛烯烴類單體可進(jìn)行自由基、陽離子、陰離子聚合 會(huì)判斷哪些單體能進(jìn)行自由基、陽離子、陰離子聚合 根據(jù)反應(yīng)條件中給出的引發(fā)劑種類即能判斷聚合反應(yīng)是自由

25、基、陽離子或陰離子聚合 Cationic polymerization: Lewis酸Lewis acid Anionic polymerization: Lewis堿 (alkali metal, metal alkyl) Living anionic polymerization why anionic polymerization can be “l(fā)iving”? 活性聚合物是指在鏈增長(zhǎng)反應(yīng)中，活性鏈直到單體全部耗盡仍保持活性的聚合物，再加入單體還可繼續(xù)引發(fā)聚合，聚合的分子量繼續(xù)增加。 在陰離子聚合反應(yīng)中，帶有相同電荷的活性鏈離子不能發(fā)生雙基終止；活性鏈負(fù)碳離子的反離子常為金屬離子，它一

26、般不能奪取鏈中的某個(gè)原子或H+而終止；活性鏈通過脫去H-離子發(fā)生鏈終止又很困難，所以當(dāng)體系中無引起鏈轉(zhuǎn)移或鏈終止的雜質(zhì)時(shí)，實(shí)際上是無終止聚合，即活性聚合。 Why autoacceleration will not occur in ionic polymerization? 活性增長(zhǎng)種帶電荷，同種電荷相斥，因此無雙基終止，不會(huì)發(fā)生自動(dòng)加速效應(yīng) why the rate of anionic polymerization is larger than that of radical polymerization? 活性增長(zhǎng)種的濃度高；無終止。 離子對(duì)增長(zhǎng)種的結(jié)合形式及其活性 In non-po

27、lar solvents, extensive association takes place at high butyllithium concentrations, the initiation and propagation rates are found to be proportional to only the 1/6 and 1/2 powers of butyllithium concentration respectively. This result has been interpreted in terms of the association equilibria wi

28、th the initiator and propagating ion pairs in equilibria with the corresponding hexamer and dimer 會(huì)判斷陰離子活性聚合用于制備嵌段共聚物時(shí)的單體加料順序從單體結(jié)構(gòu)判斷） Distinguishing between radical, cationic, and anionic polymerizations 如分子量和聚合時(shí)間的關(guān)系、引發(fā)劑、轉(zhuǎn)化率和聚合時(shí)間的關(guān)系等 Ring-opening polymerization 環(huán)狀單體在引發(fā)劑作用下形成線型聚合物的過程。 Polymerizabilit

29、y （容易開環(huán)聚合的程度）: 3, 4 8 7, 5 開環(huán)聚合的性質(zhì)？Chapter 6 Coordination polymerization Composition of Ziegler-Natta catalysts （ Ziegler-Natta催化劑的組成）催化劑的組成） Ziegler-Natta catalysts are usually composed of main catalyst and co-catalyst: Compounds of Group IV-VIII transition metal: （主引發(fā)劑是（主引發(fā)劑是IV-VIII族過渡金屬化族過渡金屬化合物）

30、合物） Co-catalyst: Group I-III organometallic compounds （共引發(fā)劑（共引發(fā)劑I-III族有機(jī)金屬化族有機(jī)金屬化合物）合物） Ziegler-Natta catalysts: Lewis酸和Lewis堿，但不是簡(jiǎn)單的加合，而是能使單體通過配位聚合形成立構(gòu)規(guī)整的聚合物 Polypropylene 配位聚合的意義，典型催化劑 Polyethylene 分類，典型催化劑 能判斷給出的單體能否進(jìn)行配位聚合 能形成哪些立構(gòu)規(guī)整聚合物 是否具有旋光活性Chapter 7 Step polymerization Characteristics: 特征 Disappearance of monomer very early in the reaction far before the production of any polymer of sufficiently high molecular weight to be of practical utility. （單體在反應(yīng)初期迅速消失，但聚合物的分子量需要較長(zhǎng)時(shí)間才能達(dá)到滿足應(yīng)用的要求） Any two species in the reaction mixture can react with ea