摘  要：以1,1,1-三羥甲基丙烷為核，2,2-二羥甲基丙酸為支化單體，對(duì)甲苯磺酸為催化劑，通過熔融縮聚法合成第三代端羥基脂肪族超支化聚酯，并用十八酸對(duì)其進(jìn)行端基改性，采用紅外光譜（FTIR）、核磁（1H NMR）、X射線衍射（XRD）、差示掃描量熱分析（DSC）以及旋轉(zhuǎn)流變儀對(duì)改性后產(chǎn)物的結(jié)構(gòu)和性能進(jìn)行了表征，研究端烷烴鏈對(duì)脂肪族超支化聚酯結(jié)晶性能和流變性能的影響。結(jié)果表明，超支化聚酯的端羥基已成功被長(zhǎng)鏈烷基所取代。超支化聚合物的結(jié)晶能力由于長(zhǎng)鏈端烷烴的有序排列而得到明顯提高。改性超支化聚酯的結(jié)晶能力主要取決于端基長(zhǎng)鏈烷烴的數(shù)量，與端羥基含量的多少無關(guān)。通過旋轉(zhuǎn)流變儀來表征超支化聚酯的流變性能，由于端烷烴鏈的纏結(jié)作用，超支化聚酯的線性粘彈區(qū)隨著端基改性程度的增大而逐漸變短；由于端十八烷基的“內(nèi)增塑”作用，使得改性后超支化聚酯的復(fù)數(shù)粘度值明顯小于改性前；改性超支化聚酯的流變特性不遵循Cox-Merz方程，改性程度越大，表觀粘度與復(fù)數(shù)粘度的偏離程度越大；端烷烴鏈數(shù)量的增多使得分子間逐漸發(fā)生了鏈纏結(jié)，相互作用力增加，粘度對(duì)剪切的依賴性增大，剪切變稀越明顯；四種改性超支化聚酯的結(jié)晶溫度接近，進(jìn)一步證實(shí)了超支化聚酯的結(jié)晶確實(shí)是由長(zhǎng)鏈端烷基的有序排列造成的，而非氫鍵的作用。

關(guān)鍵詞：超支化聚酯；十八酸；結(jié)晶性能；流變性能；鏈纏結(jié)

Effect of the terminal alkyl groups on the crystallization and rheological properties of aliphatic hyperbranched polyesters

Abstract：Hyperbranched polyesters based on 1,1,1-trimethylolpropane as core and 2,2-bis(hydroxymethyl)propionic acid as branched monomer were end-capped with stearic acids. The initial and modified polymers were characterized by Fourier transform infrared spectrum(FTIR), nuclear magnetic resonance spectroscopy(1H NMR), x-ray diffraction(XRD), differential scanning calorimeter(DSC) and rotary rheometer to investigate the effects of alkyl chains on crystallization and rheological properties of aliphatic hyperbranched polyesters. The results indicated that the amount of alkyl chains greatly influenced the properties of these polymers. The results of FTIR and 1H NMR showed that hyperbranched polymers were modified successfully. The improvement of crystallization properties can by realized by the ordered arrangement of long alkyl chains. The ability of crystallization of the modified hyperbranched polyesters mainly depends on the amount of alkyl chains. The rheological properties of hyperbranched polyesters were determined by rotary rheometer. Because of the entanglement of alkyl-terminated chains, the LVE region became shorter gradually with the improvement of the degree of modification, and the complex viscosity of hyperbranched polyesters was significantly lower than before. The Cox-Merz rule did not hold for the hyperbranched polyester, and with the improvement of the degree of modification, the hyperbranched polyester showed deviations from the rule due to the long alkyl chains in the terminal groups. After modification, the long alkyl chains weaken the hydrogen bonds, which reduced the dependence of viscosity on shear. The relationship between the shear viscosity and shear rate was dependent on the chain entanglements.With the improvement of the degree of modification, chain entanglements became more serious. The crystallization temperature of four kinds of modified hyperbranched polyesters was close, which further confirmed that the improvement of crystallization properties of the hyperbranched polyester can be realized by ordering the arrangement of the long alkyl chains in the terminal groups.

Key words：hyperbranched polyester; stearic acid; crystallization properties; rheological properties; chain entanglements

目  錄

摘要 I

目錄 III

術(shù)語表 1

1緒論 2

1.1超支化聚合物 2

1.1.1超支化聚合物的結(jié)構(gòu) 2

1.1.2超支化聚合物的合成 3

1.1.2.1 縮聚 4

1.1.2.2活性聚合 4

1.1.2.3多支化開環(huán)聚合 5

1.1.2.4離子型聚合 6

1.1.3 超支化聚合物的性能 6

1.1.3.1 溶解性 6

1.1.3.2 粘度 6

1.1.3.3玻璃化轉(zhuǎn)變溫度(Tg) 7

1.1.3.4流變學(xué)性質(zhì) 7

1.1.3.5結(jié)晶性能 7

1.1.3.6 膠束特性 8

1.2 課題研究的目的和意義 8

2實(shí)驗(yàn)部分 9

2.1實(shí)驗(yàn)原料 9

2.2 超支化聚酯的合成 9

2.3 超支化聚酯的提純 11

2.4 實(shí)驗(yàn)儀器及測(cè)試條件 11

2.4.1 紅外(FTIR) 11

2.4.2 核磁(1H NMR) 11

2.4.3 廣角X射線衍射(WAXD) 11

2.4.4 差示掃描量熱分析(DSC) 12

2.4.5 流變測(cè)試 12

3結(jié)果與討論 13

3.1 超支化聚酯的結(jié)構(gòu)表征 13

3.2 超支化聚酯的結(jié)晶性能 15

3.3 超支化聚酯的熱性能 16

3.4 超支化聚酯的流變性能 17

3.4.1線性粘彈區(qū)（LVE）的確定 17

3.4.2 頻率掃描 18

3.4.3 溫度掃描 22

3.5 改性超支化聚酯的纏結(jié)、松弛與結(jié)晶 22

4 結(jié)論 25

參考文獻(xiàn) 26

致謝 30