Polymer Characterization by On-Line GPC/NMR

通过在线 GPC/NMR 表征聚合物

• 批准号: 08405059
• 负责人: HATADA Koichi
• 金额: $ 20.1万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08405059/
• 关键词: Size Exclusion Chromatography; Gel Permeation Chromatography; Nuclear Magnetic Resonance; Molecular Weight Distribution; LC-NMR; EPDM; Poly (methyl methacrylate); Stereocomplex; 高分子錯体; GPC; 末端基定量; 共重合組成; 分子量測定

(1) A gel peameation chromatograph coupled to a ^1H NMR spectrometer (on-line GPC/NMR) was used to analyze molecular weight distributions of isotactic PMNAs with M_n ranging from 3.27*10^3 to 2.22*10^4. The molecular weight of the polymer in flowing eluate was determined directly (without a conventional calibration procedure) from the relative intensity of NMR signals due to the end-group and repeating units. The molecular weight distribution determined in this manner was proved to be accurate by SEC-NMR experiments on uniform isotactic PMMAs consisting of exactly 23,40, and 80 repeating units. Investigation was also undertaken to optimize flow rate and NMR parameters for quantitative GPC/NMR measurements. The signal-to-noise ratio of 750 MHz GPC/NMR spectra was 9.2 times that obtained previously with 500 MHz GPC/NMR operated under similar conditions.(2) Chemical compositions in ethylene-propylene- (2-ethylidene-5-norbornene) terpolymers (EPDM) were investigated by 750 MHz on-line GPC/ … More NMR.Comparison of the chromatograms obtained by monitoring the CH_2 and CH_3 resonances in a terpolymer sample showed clearly the ethylene/propylene ratio as a function of molar mass. The measurements were carried out with continuous flow of eluent (chloroform-d, 0.2mL/min). Molar mass dependence of a small amount (0.6-1.1mol%) of 2-ethylidene-5-norbornene units in a terpolymer was determined by GPC/NMR using the stop-and-flow technique.(3) Stereocomplexation between uniform isotactic (mm=100%) and syndiotactic (rr=98%) 46mers of MMA was studied by 750 MHz on-line GPC/NMR.A blend of st-46mer and it-46mer (st-/it-=0.61) in acetone/acetone-d_6 (95/5) was allowed to stand at -15ﾟC for 24h, and then subjected to the GPC/NMR measurements (column temp., -15ﾟC ; probe temp., 45ﾟC). Besides the elution peak due to non-complexed 46mers, a peak due to stereocomplex was observed at a high MW region in the chromatogram. The GPC curves recorded by monitoring it-OCH_3 and st-OCH_3 resonances showed clearly that the non-complexed part consisted essentially of it-46mer and st-/it- ratio in the stereocomplex part was 1.5 to 1.7. When probe temperature was adjusted to the column temperature (-15ﾟC), no resonance due to it-46mer was observed in the GPC/NMR spectra of the stereocomplex part because of the loss of segmental mobility. Less

(1)采用凝胶层析联用^1H核磁共振谱仪（在线GPC/NMR），分析了M_n为3.27*10^3 ~ 2.22*10^4的等规PMNAs的分子量分布。流动洗脱液中聚合物的分子量直接由端基和重复单元引起的核磁共振信号的相对强度确定（没有传统的校准程序）。在由23、40和80个重复单元组成的均匀等规pmma上，通过SEC-NMR实验证明了用这种方法确定的分子量分布是准确的。研究还进行了优化流量和核磁共振参数定量GPC/核磁共振测量。750 MHz GPC/NMR谱的信噪比是500 MHz GPC/NMR谱在相同条件下的9.2倍。(2)利用750 MHz在线GPC/…More NMR研究了乙烯-丙烯-（2-乙基-5-降冰片烯）三元共聚物（EPDM）的化学组成。通过监测三元共聚物样品中CH_2和CH_3的共振得到的色谱图的比较，清楚地表明乙烯/丙烯比是摩尔质量的函数。在连续流动的洗脱液（氯仿-d， 0.2mL/min）下进行测量。采用停止-流动技术，用GPC/NMR测定了三元共聚物中少量（0.6-1.1mol%） 2-乙基-5-降冰片烯单元的摩尔质量依赖性。(3)利用750 MHz在线GPC/NMR研究了均匀等规（mm=100%）和共规（rr=98%） 46mers MMA的立体配位作用。将st-46mer和it-46mer （st-/it-=0.61）在丙酮/丙酮-d_6（95/5）中放置在-15 C下24h，然后进行GPC/NMR测量（柱温，-15 C；探针温度，45 C）。在色谱的高MW区，除了非络合物的洗脱峰外，还观察到一个立体络合物的洗脱峰。监测it- och_3和st- och_3共振记录的GPC曲线清楚地表明，非络合部分主要由it-46mer组成，立体络合部分st-/it-比值为1.5 ~ 1.7。当探针温度调整到柱温（-15ºC）时，由于节段迁移率的损失，在立体配合物部分的GPC/NMR光谱中没有观察到由it-46mer引起的共振。少

项目成果

Tatsuki Kitayama, Tomohiro Hirano, Takatsune Yanagida, Masato Tabuchi, Koichi Hatada: "Methacrylate Polymerization with Binary Initiators for Multiple Control of Polymer Structures" Macromol.Symp.(in press).

Tatsuki Kitayama、Tomohiro Hirano、Taktsune Yanagida、Masato Tabuchi、Koichi Hatada：“使用二元引发剂进行甲基丙烯酸酯聚合，用于聚合物结构的多重控制” Macromol.Symp.（出版中）。

Tatsuki Kitayama: "Methacrylate Polymerization with Binary Initiators for Multiple Control of Polymer Structures" Macromolecular Symposia,in press.

Tatsuki Kitayama：“用二元引发剂进行甲基丙烯酸酯聚合以实现聚合物结构的多重控制”高分子研讨会，出版中。

Koichi Ute, Ryo Niimi, Shin-ya Hongo, Koichi Hatada: "Direct Determination of Molecular Weight Distribution by Size Exclusion Chromatography with 750 MHz ^1H NMR Detection (On-line SEC-NMR)" Polym.J.30. 439-443 (1998)

Koichi Ute、Ryo Niimi、Shin-ya Hongo、Koichi Hatada：“使用 750 MHz ^1H NMR 检测（在线 SEC-NMR）通过尺寸排阻色谱法直接测定分子量分布”Polym.J.30。

右手 浩一: "均一オリゴマーの単結晶-高分子立体化学の精密化をめざして" 高分子. 46. 749-750 (1997)

Koichi Right Hand：“均相低聚物的单晶 - 旨在完善聚合物的立体化学”Kobunshi 46. 749-750 (1997)。

Tatsuki Kitayama: "Methacrylate Polymerization with Binary Initiators for Multiple Control of Polymer Structures" Macromolecutar Symposia.

Tatsuki Kitayama：“用二元引发剂进行甲基丙烯酸酯聚合以实现聚合物结构的多重控制”高分子研讨会。