Curing Systems of PBT Polyether Polyurethane with Different Active Hydrogen Components
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摘要: 以3, 3-双叠氮甲基氧杂环丁烷-四氢呋喃共聚醚(PBT)为聚醚聚氨酯的软段、甲苯-2,4-二异氰酸酯(TDI)为固化剂、一缩二乙二醇(DEG)为扩链剂、三羟甲基丙烷(TMP)为交联剂,利用二步法制备了不同活泼氢组分的PBT聚醚聚氨酯。采用傅里叶变换红外光谱(FT-IR)仪、差示扫描量热(DSC)仪、电子万能试验机及溶胀率测试仪,对PBT/TDI、PBT/TDI/DEG、PBT/TDI/TMP/和PBT/TDI/DEG/TMP体系进行了固化反应动力学及力学性能的研究。结果表明:PBT/TDI、PBT/TDI/DEG、PBT/TDI/TMP/和PBT/TDI/DEG/TMP体系的固化反应均为二级反应,活化能分别为135.984、165.573、164.933、164.292 kJ/mol。加入DEG可显著提高黏合剂基体的断裂伸长率,但拉伸强度下降;加入TMP能提高黏合剂基体的拉伸强度,但断裂伸长率下降;同时加入DEG和TMP的黏合剂基体拉伸强度提高,断裂伸长率有所下降。DEG和TMP能不同程度地提高固化体系的交联密度。Abstract: PBT polyether polyurethanes with different active hydrogen components were prepared by a two-step method using 3, 3-diazymoxy-tetrahydrofuran copolymer (PBT) as the soft segment of polyether polyurethanes, toluene diisocyanate (TDI) as the curing agent, diethylene glycol (DEG) as the chain extender and trimethylol propane (TMP) as the crosslinking agent. The curing reaction kinetics and mechanical properties of PBT/TDI, PBT/TDI/DEG, PBT/TDI/TMP and PBT/TDI/DEG/TMP systems were studied by Fourier Transform Infrared Spectroscopy (FT-IR), Differential Scanning Calorimeter (DSC), electronic universal testing machine and swelling ratio test. The results show that the curing reactions of PBT/TDI, PBT/TDI/DEG, PBT/TDI/TMP/ and PBT/TDI/DEG/TMP systems are second-order reactions, and the activation energies of these systems are 135.984, 165.573, 164.933 and 164.292 kJ/mol, respectively. The addition of DEG can significantly increase breaking elongation of the adhesive matrix, but the tensile strength decreases; The addition of TMP can improve the tensile strength of the adhesive matrix and reduce breaking elongation; when DEG and TMP exist simultaneously, the tensile strength of the adhesive matrix increased and the elongation at break decreased. DEG and TMP can both improve the crosslinking density of the curing systems.
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Key words:
- PBT propellant /
- curing reaction /
- reaction kinetics /
- mechanical property /
- active hydrogen
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表 1 4组不同活泼氢组分的PBT固化体系
Table 1. PBT curing system with four different active hydrogen components
Curing system Component R 1 PBT/TDI 1.2 2 PBT/TDI/DEG 1.2 3 PBT/TDI/TMP 1.2 4 PBT/TDI/DEG/TMP 1.2 R—Curing coefficient 表 2 不同固化体系和不同升温速率下的Tp
Table 2. Tp of the different curing system and heating rate
Heating rate/
(℃·min−1)Tp/℃ System 1 System 2 System 3 System 4 5 247 250 249 251 10 258 259 258 259 15 262 264 263 265 20 267 269 268 269 表 3 不同固化体系的固化反应动力学参数
Table 3. Curing reaction kinetic parameters of the different curing system
Curing system Ea/(kJ·mol−1) A/s−1 n k/(kg·mol−1·s−1)1) 1 135.984 1.385×1013 0.939 6.47×10−10 2 165.573 1.270×1016 0.949 1.36×10−10 3 164.933 1.180×1016 0.949 1.59×10−10 4 164.292 8.930×1015 0.949 1.51×10−10 1) Reaction temperature is 60 ℃ 表 4 不同固化体系的力学性能
Table 4. Mechanical properties of the different curing system
Curing system Tensile strength/MPa Breaking elongation/% Initial tensile modulus/MPa 1 1.0950 10.3930 0.3210 2 0.9280 15.2740 0.2863 3 2.0940 5.7560 0.3412 4 1.9080 7.0710 0.5452 表 5 不同固化体系溶胀系数
Table 5. Swelling coefficient of the different curing system
Curing system qv 1 5.20 2 4.93 3 4.36 4 3.76 -
[1] 庞爱民. 固体火箭推进剂理论与工程[M]. 北京: 中国宇航出版社, 2014. [2] ZIA K M, BARIKANI M, BHATTI I A, et al. Synthesis and thermomechanical characterization of polyurethane elastomers extended with α, ω-alkane diols[J]. Journal of Applied Polymer Science, 2008, 109(3): 1840-1849. doi: 10.1002/app.28242 [3] LIAW D. The relative physical and thermal properties of polyurethane elastomers: Effect of chain extenders of bisphenols, diisocyanate, and polyol structures[J]. Journal of Applied Polymer Science, 1997, 66(7): 1251-1265. doi: 10.1002/(SICI)1097-4628(19971114)66:7<1251::AID-APP5>3.0.CO;2-F [4] HIRAOKA K, TAKESUE M, YOKOYAMA T. The thermal and mechanical properties and the ionic conductivity of cationic polyurethane elastomers with pendant trimethylammonium group[J]. Polymer Journal, 2004, 36(1): 1-9. doi: 10.1295/polymj.36.1 [5] 周水平, 吴芳, 唐根, 等. 含能交联剂对PBT高能推进剂力学性能的影响[J]. 化学推进剂与高分子材料, 2016, 14(4): 54-59. [6] 张波, 段华军, 陈杰. PTMG-TMP混合扩链交联对聚氨酯树脂力学性能的影响[J]. 复合材料学报, 2018, 35(1): 44-49. [7] 李洋, 姜磊, 尹必文, 等. PBT基钝感低特征信号推进剂的力学性能优化研究[J]. 固体火箭技术, 2021, 44(4): 479-485. [8] 王海波. 丁羟四组元复合固体推进剂固化体系研究[D]. 长沙: 湖南大学, 2007. [9] 邱磊, 王鸿宇, 代颖军, 等. 非等温DSC研究PBT/TDI固化反应动力学[J]. 化学推进剂与高分子材料, 2020, 18(1): 38-41. [10] 徐婉, 邓剑如, 张丽. NEPE推进剂中活泼氢组分的固化反应动力学研究[J]. 固体火箭技术, 2010, 33(5): 560-563. doi: 10.3969/j.issn.1006-2793.2010.05.018 [11] 郑启龙. 叠氮类粘合剂环氧固化体系及其在火药中的应用研究[D]. 南京: 南京理工大学, 2017. [12] 吴艳光, 罗运军, 葛震. GAP型交联改性双基推进剂黏合剂的力学性能[J]. 火炸药学报, 2012(2): .66-69. [13] 赵长才, 鲁国林, 王北海. 二醇类扩链剂对丁羟推进剂力学性能的影响[J]. 固体火箭技术, 2000(4): 23-28. doi: 10.3969/j.issn.1006-2793.2000.04.007 [14] ZHAI J X, ZHANG N, GUO X Y, et al. Study on bulk preparation and properties of click chemistry end-crosslinked copolyether elastomers[J]. European Polymer Journal, 2016, 78: 72-81. doi: 10.1016/j.eurpolymj.2016.03.009 [15] FEI B, CHEN C, PENG S W, et al. FT-IR study of poly(propylene carbonate)/ bisphenol a blends[J]. Polymer International, 2004, 53(12): 2092-2098. doi: 10.1002/pi.1633 [16] 蔡如琳, 吴倩, 王敏, 等. PBT基叠氮型聚氨酯弹性体的形态结构与微相分离[J]. 固体火箭技术, 2019, 42(4): 488-492, 498. [17] 左海丽, 詹国柱, 楼阳, 等. PBT弹性体微相分离及对其力学性能的影响研究[J]. 上海航天, 2018, 35(4): 134-141. [18] 刘晶如, 罗运军. 非等温DSC研究Al/HTPB/TDI体系的固化反应动力学[J]. 含能材料, 2009, 17(1): 83-86. doi: 10.3969/j.issn.1006-9941.2009.01.020 [19] KISSINGER H E. Reaction kinetics in differential thermal analysis[J]. Analytical Chemistry, 1957, 29(5): 1702-1706. [20] OZAWA T. A new method of analyzing thermo-gravimetric data[J]. Bulletin of the Chemical Society of Japan, 1965, 3(11): 1881-1886. [21] CRANE L W, DYNES P J, KAELBLE D H. Analysis of curing kinetics in polymer composites[J]. Polymer Letter Edition, 1973(11): 533-540. [22] 王晓霞, 王成国, 贾玉玺, 等. 热固性树脂固化动力学模型简化的新方法[J]. 材料工程, 2012(6): 67-70. doi: 10.3969/j.issn.1001-4381.2012.06.015 [23] 菅晓霞, 田书春, 宋育芳, 等. 硬段结构对3, 3-双(叠氮甲基)环氧丁烷-四氢呋喃共聚醚弹性体力学性能的影响[J]. 高分子材料科学与工程, 2017, 33(12): 22-25, 30. [24] 魏欣, 李夏, 于丰, 等. 扩链交联剂对水性聚氨酯乳液性能的影响[J]. 聚氨酯工业, 2017, 32(4): 24-26, 30. [25] 刘贺, 张晓青, 马凤国. 发泡剂和扩链剂/交联剂对聚酯型聚氨酯泡沫的影响[J]. 合成材料老化与应用, 2019, 48(1): 25-28. [26] 邓剑如, 张习龙, 徐婉, 等. NEPE推进剂粘合剂配方设计方法[J]. 固体火箭技术, 2014, 37(2): 238-240. [27] 丁腾飞, 翟进贤, 郭晓燕, 等. 两种固化剂对PBT弹性体力学性能的影响[J]. 含能材料, 2020, 28(1): 56-61. -