第7章离子聚合

1、 离离 子子 聚聚 合合 5.1 55.2 1.A BCH2 CHR+CH2 CRA BHHn l 烯烃烯烃CH2 CH2CH2 CHCH3CH2 CHC2H5H( kJ/mol) 640757 791H+CH2 CHC2H5CH3 CHC2H5(CH3)3CCH2 CCH3CH3CH2 C CH2 CCH3CH3CH3CH3l CH2 COHCH2 COHRR:ORCH2 CH 2. H2SO4，H3PO4，HClO4， CF3COOH，CCl3COOHl H AHAH ACH2 CHXCH3 CHXA+ CH3 CHXACH3 CHXAl (CH3)3C Cl(CH3)3C Cln 如：如

2、：BF3 + H2O H (BF3OH)CH3CH2 C + CH3H (BF3OH)CH3CH3 C CH3(BF3OH) BF3 AlCl3 TiCl4 SnCl4 ： 水水 ：乙酸：乙酸 ：甲醇：甲醇 50 ：1. 5 ：1 SnCl4 + RX R (SnCl5)CH3CH2 C + CH3R (SnCl5)CH3R CH2 C CH3(SnCl5)(BF3OH)CH3 CH2 C CH3+ H2O+ H (BF3OH)CH3 CH2 C OH CH3+ H2OBF3H (BF3OH)H2O(H3O) (BF3OH)发发 I2 +I2I (I3)CH3C (ClO4) + M OCH3

3、CM (ClO4)O3 3 KC + RHH (CR)H (CR) + M HM (CR)ki CH2 CHN+ TCE CH CH2NTCE 引发活化能低，引发活化能低， 8. 4 21 kJ/mol，故引发速率很快，故引发速率很快（与自由基慢引发（与自由基慢引发Ed = 105 150 kJ/mol 截然不同截然不同) )K = H (CR) C RHC RHH (CR) = K Ri = ki C RH M = ki K C RH MH (CR) Ri = ki : :HM (CR) + n MHMnM (CR) kpRp = kp HM (CR) M：: CH2 CH CH3 CH C

4、H3 CH2 CH2 C CH3 CH3 l H CH2 C CH3 CH3 CH2 C CH3 CH3 CH3 (BF3OH)CH3CH2 CCH3+H+ n(BF3OH)H CH2 C CH3 CH3 CH2 C CH3 CH3 CH2 CH3CH3 CCH3+n Rtr,m = ktr,m HM (CR) M：nn+1ktr,mHM (CR)+MM+HM M (CR) HMnM (CR)Mn+1+H (CR)kt:nH CH2 C CH3 CH3 CH2 C CH3 CH3 CH3 (BF3OH)+H CH2 C CH3 CH3 CH2 C CH2 CH3 CH3 H (BF3OH)n：

5、u HMnM (CR)HMnM(CR)u CH3 CH2 CCH3(BF3OH)CH3 CH2 CCH3OH + BF3Rt = kt HM (CR) u HMnM (CR)+ XAHMnMA + X (CR)ktr,sOO+2 HMnM (CR)+(CR)2OHHO2 HMnM2 ： 建立稳态建立稳态Ri = ki H (CR) M增长增长Ri = K ki C RH MMHM (CR) Rp = kp 终止终止引发剂引引发剂引发生成碳发生成碳阳离子的阳离子的反是控制反是控制速率反应速率反应Ri = RtK ki C RH MHM (CR) = ktn 动力学方程动力学方程引发引发:Rt =

6、 kt HM (CR) ：Rp = C RH M2K ki kpktl Xn =RPRt=kp HM (CR) Mkt HM (CR) =kPktMl Xn1=kPktM+ CM+ CSMS1=MCMktr,MkP=ktr,m HM (CR) MHM (CR) kp =Rtr,MRPXn =l kp ( l / mols) 7. 6 100 kt 4.9102 (s1) 10 7 ( l / mols) kp / kt 102 kp / kt1/2 102 活性种浓度活性种浓度 C* 103 M 108 Rp阳 Rp自5 5l A B A B A B A B +l l l l ki kR =

7、kp kt e-(Ei + Ep - Et) / RT At Ap = kR Ai 21 41.8 kJ / mol = Ei + Ep - Et l e-(Ep - Et) / RT At Ap = k XnXnk = Ap Atr,M e-(Ep - Etr,m) / RT XnE = Ep - Etr,M XnE = Ep - Et MXn =kPktXn =kPktr,M5.3 n具有吸电子取代基的烯类单体原则上可以进具有吸电子取代基的烯类单体原则上可以进行阴离子聚合行阴离子聚合n 能否聚合取决于两种因素能否聚合取决于两种因素l是否具有是否具有 共轭体系共轭体系 吸电子基团并具有吸电子

8、基团并具有 共轭体系，能够进行阴离共轭体系，能够进行阴离子聚合，如子聚合，如AN、MMA、硝基乙烯硝基乙烯 吸电子基团并不具有吸电子基团并不具有 共轭体系，则不能进行共轭体系，则不能进行阴离子聚合，如阴离子聚合，如VC、VAcl与吸电子能力有关与吸电子能力有关 +e 值越大，吸电子能力越强，易进行阴离子聚合值越大，吸电子能力越强，易进行阴离子聚合1.1.阴离子聚合单体阴离子聚合单体A BA B单体自由基阴离子单体自由基阴离子Na CH2 CHXNa + CH2 CHXCH CH2XNa XCH CH2Na 2XCH CH2 CH2 CH Na XNa 双阴离子活性中心双阴离子活性中心Na +

9、Na THFNa CH2 CH+ CH CH2Na CH CH2Na CH2 CHNa + Na CH CH22 K 2 + 2 2 NH3KNH2+ H2KNH2K + NH2NH2CH2 CH+ CH2 CHH2Nl金属烷基化合物金属烷基化合物 引发活性与金属的电负性有关引发活性与金属的电负性有关 金属的电负性如下金属的电负性如下 K Na Li Mg Al R3N+ CH2 CHX R3NCH2 CHX X CH2 CH CH2 CHR3NX n 3. ：CH2CHCHCHNa H . . CH2CHCH CH+ H . . . Na CH2C CH CHH CH2CH. . Na + H CH2CH2. . + CH2C CH CHNa CHX A + CO2CHCOOA X CHCOOHX H+ + CHX A CH2 CH2O CHCH2CH2OX A 端胺基化反应端胺基化反应CH C NH R NH2X O H+ CH C N R NCOX OA A CH3O + X CHCH2CH2OHCH3OH O C N R NCO+ A X CH l ：CMnnMMnXnn2 C4H9-M Li (C4H9M Li )2 + C4H9M L