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Synthesis and Properties of Novel Aromatic Polyamides Containing Bulky Xanthene and Trifluoromethyl Pendants

Author: MaChunXin
Tutor: ShengShouRi
School: Jiangxi Normal University
Course: Polymer Chemistry and Physics
Keywords: Polyaramides Terpolymerization Trifluoromethyl side groups The structure of the xanthene ring-shaped (cardo) 9,9 - bis ( 4 - hydroxyphenyl ) xanthene 9,9 - bis [ 4 - (4 - amino - 2 - (trifluoromethyl) phenoxy ) phenyl] xanthen 9,9 - bis (4 - chloro- formylphenoxy phenyl ) xanthene Synthesis and Characterization
CLC: O633.22
Type: Master's thesis
Year: 2010
Downloads: 18
Quote: 1
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Abstract

This article first of recent years polyaramide polyamide performance, development history and current status of synthesis and modification, the polyaramide the development trend, and the aromatic polyamide copolymer Research Progress gives a brief introduction, the paper consists of five main parts : 1 The base monomer 9,9 - two (4 - hydroxyphenyl) the xanthene (BHPX) the summary of the synthesis method and improvements. My laboratory traditional method is: the xanthone was refluxed under conditions of excess SOCl2, and 2-3 drops of DMF solubilizing reaction 8h after, the excess of SOCl2 was distilled off; After cooling to room temperature the xylene was added and the appropriate excess phenol, after reflux for 10h, the xylene was distilled off and the excess of phenol under reduced pressure, and then recrystallized. While this method there are a large number of excess phenol internal double teams on the massive product, can not be distilled clean. Required the crude product was recrystallized twice more in order to achieve high purity, the yield is low (below 75%), and time-consuming. I on the law is improved, prior to recrystallization, the crude product is first soaked in hot toluene, and then simply recrystallized once to a high purity 9,9 - two (4 - hydroxyphenyl) xanthene a yield of up to 85%. 2 to a novel aryl diamine, 9,9 - bis [4 - (4 - amino - 2 - (trifluoromethyl) phenoxy) phenyl]-xanthene (BTFAPX) and a series of aryl dicarboxylic acid chloride Low The solution polycondensation prepared several novel containing a trifluoromethyl substituent and huge xanthene cardo structure polyaramide. Class polyaramide having a multifaceted excellent performance and good workability. The resultant series of polymers, the logarithmic ratio of the viscosity coefficient at between 0.65-1.01 dL / g, Tg ranging from 235-284 ℃ between the tensile strength of 65-95 MPa, a tensile modulus as 1.9-2.5 GPa breaking elongation 6-9%. Such polymers in nitrogen and 10% weight loss in the air in the range of 495-532 ° C and 476-510 ° C respectively. 800 ° C into char yield greater than 55% in nitrogen. Almost all of such polymers can be dissolved in N, N-dimethyl formamide (DMF), N, N-dimethyl-acetic acid amide (DMAC), dimethyl sulphone (DMSO), N-methyl-pyrrolidone ( NMP) and other highly polar aprotic solvent, and even also be dissolved in a polar aprotic solvent (such as tetrahydrofuran, pyridine, etc.) among. Shop to the DMAc solution of such polymer films, having a high optical permeability, and a low dielectric constant (under the conditions of 100 Hz for 3.65-4.03) and a lower hygroscopicity ( soaked in deionized water at normal temperature for 3 days, the water absorbency of 0.56-1.14%). 3 to a novel aryl dicarboxylic acid chloride 9,9 - bis (4 - chloro-formylphenoxy phenyl) xanthene (BCPX) and a series of the trifluoromethyl-containing aromatic diamine of the low temperature solution polycondensation, prepared xanthene cardo structure containing trifluoromethyl side groups and with the huge volume of several new polyaramide. The class polyarylamides larger molecular weight, excellent heat resistance, mechanical properties, optical properties, electrical properties and good processability. The resultant series of polymers, the logarithmic ratio of the viscosity coefficient ranged from 0.77-1.31 dl / g between the glass transition temperature (Tg) ranging between 240-258 ℃, a tensile strength of 81-100 MPa, tensile modulus an amount of 1.6-2.1 GPa, a breaking elongation of 8-12%. Such polymers in nitrogen and air 10% weight loss in the range of 484-517 ° C and 410-456 ° C in nitrogen 800 ° C into the char yield is greater than 55%. Almost all of such polymers can be dissolved in N, N-dimethyl acetamide (DMAc), N, N-dimethyl formamide (DMF), N-methyl pyrrolidone (NMP), dimethyl sulfoxide ( DMSO), strongly polar aprotic solvent, or even in a polar aprotic solvent (such as tetrahydrofuran, pyridine, etc.), and such polymers are also most soluble. Shop to the DMAc solution of such polymer films, having a high optical permeability, low dielectric constant (under the conditions of 100 KHz, for 3.34-3.65) and a lower moisture absorption (in deionized soaked in water at normal temperature for 3 days, the water absorbency of 0.76-1.91%), especially excellent in transparency, and its initial translucent wave length 325-345nm. 4 9,9 - two [4 - (4 - amino - 2 - (trifluoromethyl) phenoxy) phenyl]-xanthene (BTFAPX), phenylenediamine (PDA) and isophthaloyl chloride (IPC the ratio of the amount of substance) three kinds of monomers, in DMAc solvent was low-temperature solution polycondensation, to adjust BTFAPX and PDA can be obtained a series of xanthene cardo structure containing a trifluoromethyl substituent and bulky polyamide terpolymer product. The results show that the copolymer has excellent heat resistance, the copolymer in nitrogen and air 10% thermal weight loss temperature (Td), respectively, in the range of 429-501 ° C and 418-476 ° C, 800 ° C in a nitrogen atmosphere. charring rate is greater than 56%; its glass transition temperature (Tg) in the 266-278 ° C, the logarithmic ratio of the coefficient of viscosity range between 0.41-0.73 dL / g, the tensile strength range of 80-99 MPa, The tensile modulus of 1.6-2.5 Gpa, the breaking elongation of 8-12%, can be dissolved in a strongly polar aprotic solvents such as NMP, DMF, DMAc, DMSO. Such copolymers hygroscopicity is not particularly desirable, soaked for three days in deionized water at room temperature, the water absorbency of 1.50-3.01% 5 1,4 - bis (4 - amino-2 - (trifluoromethyl) phenoxy yl) the benzene (BFTAB), phenylenediamine (PDA) and 9,9 - bis (4 - (chloro-formylphenoxy) phenyl) xanthene (BCPX) three kinds of monomers, low-temperature solution in DMAc solvent the ratio of the amount of the polycondensation, the substance adjusting BTFAB and PDA can be obtained a series of xanthene structure containing trifluoromethyl-side group and a huge volume of a polyamide terpolymer product. The results show that the copolymer has excellent heat resistance, the copolymer in nitrogen and air 10% thermal weight loss temperature (Td), respectively, in the range of 525-486 ° C and 504-423 ° C, 800 ° C in a nitrogen atmosphere. charring rate is greater than 53%; logarithmic ratio of viscosity coefficient ranged from 0.82-1.31 dL / g, glass transition temperature (Tg) of 247-288 ° C, a tensile strength of 79-102 MPa and The tensile modulus of 1.8-2.5 Gpa, the breaking elongation of 8-16%, all such copolymers are soluble in NMP, DMF, DMAc, DMSO, THF, etc. Most common polar aprotic solvents. Such copolymers also has a low hygroscopicity, immersed in deionized water at room temperature for 3 days, and the water absorption ratio of 0.96-1.72%.

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CLC: > Mathematical sciences and chemical > Chemistry > Polymer chemistry ( polymer ) > Miscellaneous Chain Polymers > Nitrogen-containing polymer chain > Polyamide
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