Jinyan Wang

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Name: 王锦艳; Wang, JinYan

Organization: Dalian University of Technology , China

Department: Department of Polymer Science and Materials

Title: Professor(PhD)

TOPICS

Applied Chemistry

Polymer

PEEK

Chemicals
References

Toughening and reinforcing of benzoxazine resins using a new hyperbranched polyether epoxy as a non-phase-separation modifier

Co-reporter:Xin Wang, Lishuai Zong, Jianhua Han, Jinyan Wang, Cheng Liu, Xigao Jian

Polymer 2017 Volume 121(Volume 121) pp:

Publication Date(Web):14 July 2017

DOI:10.1016/j.polymer.2017.05.069

•A novel hyperbranched epoxy has been synthesized and used as a toughener for benzoxazine.•Simultaneous improvement of each performance is achieved in samples containing 3% and 5% loading.•No-phase separation happens in the cured hybrid system.•The toughening mechanism was mainly attributed to incorporation of “intramolecular cavities”.A novel hyperbranched polyether epoxy (HBPEE) bearing a stiff fluorene unit and flexible aliphatic chains has been synthesized using a one-pot approach and used as a toughener for bis-benzoxazine resin (MDA-BOZ). Effects of loadings and molecular weight of HBPEE on curing behavior, rheology properties, static mechanical, dynamic mechanical and thermal properties of the hybrid systems have been studied. Results show hybrids containing medium-Mn (i.e. ∼3900) HBPEE-2 modifier possesses optimal comprehensive properties. Synchronous improvement of impact strength, flexural strength and storage modulus was found in hybrids containing 5% HBPEE-2 and 5% HBPEE-3, where HBPEE served as a non-phase-separation modifier confirmed by SEM and DMA. Notably, there was a 2.8-fold improvement in impact strength for hybrids containing 10% HBPEE-2, compared to the same properties of samples without HBPEE. This was achieved without any compromise of flexural modulus, flexural strength, E′, thermal stability and glass transition temperature (Tg). The results demonstrate that multiple factors, such as enhanced crosslinking density (ve), rigidity of the toughener, reduced hydrogen bond network and higher fractional free volume, contributed to such improvement.Download high-res image (163KB)Download full-size image

Poly(phenylene-carborane) for boron-carbide/carbon ceramic precursor synthesized via nickel catalysis

Co-reporter:Shengli Cheng, Kuanyu Yuan, Xin Wang, Jianhua Han, Xigao Jian, Jinyan Wang

Polymer 2017 Volume 115(Volume 115) pp:

Publication Date(Web):21 April 2017

DOI:10.1016/j.polymer.2017.03.036

•A poly(phenylene-carborane) (PPB) was synthesized via Ni(0)-catalyzed polymerization.•PPB exhibited excellent thermal and thermo-oxidative stability.•PPB has proven to be excellent precursors to boron-carbide/carbon ceramic materials.•The ceramics showed excellent thermo-oxidative stability.High thermally and thermo-oxidatively stable poly(phenylene-carborane) (PPB) was synthesized via Ni(0)-catalyzed polymerization of bis(aryl chloride) monomer containing carborane. This polymer was soluble in THF and NMP at room temperature, thus allowing molecular weight and spectroscopic analysis. Number-average molecular weight determined by 1H-NMR spectroscopy was 5.4 × 103 g/mol. The crystalline character of PPB was verified by XRD analysis. This polymer exhibited excellent thermal and thermo-oxidative stability with 5% weight loss temperature to be 707 °C and >1000 °C in nitrogen and air, respectively. High char yields of 93.2% and 97.9% were obtained at 1000 °C in nitrogen and air, respectively. Additionally, PPB has proven to be excellent sing-source precursor to boron-carbide/carbon ceramic materials with high ceramic yields in the range of 91.1%–92.6%. According to XRD analysis, boron carbide crystallization for PPB occurred between 1000 and 1200 °C.Download high-res image (306KB)Download full-size image

Oxidatively stable thermosets derived from thermal copolymerization of acetylene-terminated imide monomer with an acetylenic monomer containing carborane

Co-reporter:Shengli Cheng, Jianhua Han, Xin Wang, Kuanyu Yuan, Xigao Jian, Jinyan Wang

Polymer 2017 Volume 115(Volume 115) pp:

Publication Date(Web):21 April 2017

DOI:10.1016/j.polymer.2017.02.070

•A novel acetylenic monomer (APCB) containing carborane was synthesized.•The thermal stability of the imide oligomers was improved by thermal copolymerization with APCB.•The mechanism of the superior thermo-oxidative stability was studied.One acetylenic monomer (APCB) containing carborane with extremely thermal and thermo-oxidative stability was synthesized and used as the thermal copolymerization component with acetylene-terminated imide monomer (m-EFDA) to improve the thermal and thermo-oxidative stability of the polyimide materials. The curing behavior of the blends of imide monomer and APCB was investigated by FT-IR and DSC. Rheometer study showed that the addition of APCB into m-EFDA reduced the minimum complex viscosity of m-EFDA and lowered the temperature of the minimum viscosity. The thermal and thermo-oxidative stability of the thermoset derived from m-EFDA was greatly improved by the addition of APCB based on thermogravimetric analysis. m-EFDA with an addition of APCB at a loading level of 50 wt% exhibited a high char yield of 91.5% at 1000 °C in air and a weight retention of 95.6% was obtained after aging in air at 400 and 500 °C for 5 h, respectively.Download high-res image (309KB)Download full-size image

Oxidative protection of carbon fibers with carborane-containing polymer

Co-reporter:Shengli Cheng, Zhihuan Weng, Xin Wang, Yunxing Pan, Xigao Jian, Jinyan Wang

Corrosion Science 2017 Volume 127(Volume 127) pp:

Publication Date(Web):1 October 2017

DOI:10.1016/j.corsci.2017.08.002

•Polymer-based oxidation-resistance coatings were prepared.•The mechanism of oxidation resistance was investigated.•Polymer-derived ceramic coating was prepared.To improve the oxidation resistance of carbon fibers, a series of carborane-containing polymer-based coatings were prepared. The oxidation resistance and microstructure of the coatings were investigated. According to XPS, FT-IR and XRD analysis, the high oxidation resistance of the polymer-based coatings was attributed to the boron oxide protective layer formed from the oxidation of carborane groups in the coating. Ceramic coatings were prepared from heat treatment of polymer-based coatings under argon at 1300 °C for 2 h. The great oxidation resistance of the ceramic coating was attributed to the existence of boron carbide in coating.

Multiple-SO3H functioned ionic liquid as efficient curing agent for phthalonitrile-terminated poly(phthalazinone ether nitrile)

Co-reporter:Zhi-Huan Weng, Yu Qi, Li-Shuai Zong, Cheng Liu, ... Xi-Gao Jian

Chinese Chemical Letters 2017 Volume 28, Issue 5(Volume 28, Issue 5) pp:

Publication Date(Web):1 May 2017

DOI:10.1016/j.cclet.2016.12.019

Combined with the advantages of low melting point, high thermal stability and strong acidity, a multiple-SO3H functioned ionic liquid (MIL) was developed successfully as a curing agent to promote the curing reaction of phthalonitrile-terminated poly(phthalazinone ether nitrile) (PPEN-Ph). The curing kinetics over differential scanning calorimetry (DSC) showed that both the initial curing temperature Tp0′ and apparent activation energy Ea’ (based on Kissinger equation) were reduced significantly over MIL (207.9 °C and 101.5 kJ/mol) compared to the common curing agent ZnCl2 (268.5 °C and 201.5 kJ/mol). Moreover, under identical curing conditions, the resulting thermosetting resin over former (Td5% = 526.1 °C) showed better thermal stability than that over latter (Td5% = 512.1 °C). These results indicated that MIL should be a good candidate as a curing agent for phthalonitrile resins.Download high-res image (139KB)Download full-size imageA multiple-SO3H functioned ionic liquid (MIL) was employed as curing agent of phthalonitrile-terminated poly(phthalazinone ether nitrile) (PPEN-Ph), both the initial curing temperature Tp0′ and apparent activation energy Ea’ were reduced significantly over MIL than the common ZnCl2, moreover, the thermal stability of resulting resin was better on former.

Effect of Poly(phthalazinone ether ketone) with amino groups on the interfacial performance of carbon fibers reinforced PPBES resin

Co-reporter:Nan Li, Lishuai Zong, Zuoqiang Wu, Cheng Liu, Jinyan Wang, Xigao Jian

Composites Science and Technology 2017 Volume 149(Volume 149) pp:

Publication Date(Web):8 September 2017

DOI:10.1016/j.compscitech.2017.06.020

In this study, novel aminated poly(phthalazinone ether ketone) (PPEK-NH2) with amino groups on main chains was synthesized by typical condensation polymerization of 4-(4-Hydroxylphenyl)(2H)-phthalazin-1-one (DHPZ), 4,4’-difluoro benzophenone (DFK), and the third active monomer, 1,5-diamino-4,8-dihydroxyanthraquinon (DDT). As a type of compatibilizer, PPEK-NH2 was utilized to modify the interface properties of carbon fibers (CF) reinforced copoly(phthalazinone ether sulfone)s (PPBES) composites. The composites were prepared by solution impregnation and compression molding, where PPEK-NH2 was distinguished by different mole ratios of DHPZ/DFK/DDT. And the effects of amino structural unit quantity in PPEK-NH2 chains on compatibility was investigated. Of all the compatibilizers, PPEK-NH2 (4) exhibits the best compatible effect. The interlaminar shear strength and flexural strength of CF/PPBES increased significantly by 15.8% and 26.2%, respectively. According to DMA test, the storage modulus and service temperature increase by 12 GPa and 7 °C, respectively. Beside, CF/PPBES/PPEK-NH2 (4) exhibits excellent mechanical behaviours with at 240 °C and 250 °C. Moreover, this composite also demonstrates excellence in hydrothermal aging tests. This method contains simple process, large-scale application potential, which offers new insights for fabricating high-performance advanced thermoplastic composites.

Amino-terminated nitrogen-rich layer to improve the interlaminar shear strength between carbon fiber and a thermoplastic matrix

Co-reporter:Nan Li, Lishuai Zong, Zuoqiang Wu, Cheng Liu, Xin Wang, Feng Bao, Jinyan Wang, Xigao Jian

Composites Part A: Applied Science and Manufacturing 2017 Volume 101(Volume 101) pp:

Publication Date(Web):1 October 2017

DOI:10.1016/j.compositesa.2017.06.023

An amino-terminated nitrogen-rich layer of poly(cyclotriphosphazene-co-melamine) (PPM) coating was used to functionalize carbon fiber (CF) to strengthen the interfacial adhesion of CF reinforced copoly(phthalazinone ether sulfone)s (PPBES) through a facile in-situ polymerization. FTIR, Raman and XPS confirm the chemical bonds between CF and PPM. SEM and dynamic contact angle tests demonstrate that PPM coating can enhance surface wettability, roughnes of CF, which can improve interlaminar shear strength and flexural strength of CF/PPBES by 23.2% and 29.3% with no discernable decrease on tensile strength of CFs. According to DMA test, storage modulus and service temperature increase by 15 GPa and 6 °C. SEM observations certify that the failure mechanism transforms from interface failure for CF/PPBES to matrix failure and fiber broken for CF-PPM/PPBES. Moreover, the successful preparation of PPM coatings on CF surface provides new insights for the fabrication of advanced thermoplastic composites from readily available components via a facile route.

Donor–acceptor copolymers containing phthalazinone–thiophene structure synthesized by low-cost copper-catalyzed Ullmann polymerization

Co-reporter:Jianhua Han, Haoyue Yin, Cheng Liu, Jinyan Wang and Xigao Jian

RSC Advances 2016 vol. 6(Issue 8) pp:6772-6781

Publication Date(Web):18 Dec 2015

DOI:10.1039/C5RA21246D

Herein, we present low-cost copper-catalyzed Ullmann polycondensation of phthalazinone based monomers containing both OH and NH groups, which provides access to polyarylethers and conjugated polymers. The synthesis of the polymers was accomplished by a combination of low activity thiophene and carbazole monomers. In particular, it was shown that a stronger base (Cs2CO3 > K2CO3) can efficiently polymerize the low activity thiophene monomer with the phthalazinone based monomer, to obtain high number-average molecular weight, up to 17.9 kDa (PDI = 2.43). Moreover, in this study, the result of reaction process monitoring revealed that the Ullmann polymerization was in favour of the radical mechanism. The reaction activity of di-halogenated monomers was found to be a crucial factor for achieving a high molecular weight polymer. Thus, the number-average molecular weight of donor–acceptor copolymers containing the phthalazinone–thiophene structure ranged from 2.2 to 9.6 kDa. The new copolymer structures were confirmed by 1H-NMR, FT-IR and GPC. Their thermal, optical, electrochemical and X-ray diffraction (XRD) properties, and density functional theory (DFT) calculations, were investigated in detail. The results show that the thiophene unit is beneficial to the π–π interaction between the polymer chains, compared to carbazole and phthalazinone units.

Nickel-catalysed Kumada polycondensation of di-functionalized Grignard reagent with aryl fluoride

Co-reporter:Jianhua Han;Lishuai Zong;Cheng Liu;Xigao Jian

Polymer International 2016 Volume 65( Issue 5) pp:526-534

Publication Date(Web):

DOI:10.1002/pi.5086

Abstract

A nickel catalyst promoted the polymerization between various Grignard reagents with 2-phenyl-4,6-bi(4-fluorophenyl)-1,3,5-triazine. The reaction scope was thoroughly investigated and fully characterized. The Sp²-C − F bond was successfully activated by the triazine group in Kumada coupling reactions. Also, di-Grignard reagents showed higher activity than mono-Grignard reagents. The reaction scope results reveal that a Grignard reagent with strong nucleophilicity and aryl fluoride with strong electrophilicity are necessary to lead to Kumada polycondensation of oligothiophenes with aryl fluoride. In this work, polymerization between di-functionalized oligothiophene Grignard reagents with aryl fluoride was first conducted. The weight-average molecular weight is high, up to 14.8 kDa. The π-conjugated polymers obtained exhibit emission colours of blue, green and yellow with efficient photoluminescence. © 2016 Society of Chemical Industry

Interaction and properties of epoxy-amine system modified with poly(phthalazinone ether nitrile ketone)

Co-reporter:Rui Liu;Qinzheng He;Lishuai Zong;Xigao Jian

Journal of Applied Polymer Science 2016 Volume 133( Issue 10) pp:

Publication Date(Web):

DOI:10.1002/app.42938

ABSTRACT

An epoxy based on the tetraglycidyl 4,4′-diaminodiphenyl- methane (TGDDM)/bisphenol A type novolac(F-51) cured with 4,4′-diaminidiphenysulfone (DDS) has been modified with Poly (phthalazinone ether nitrile ketone)(PPENK). The interaction between the PPENK and epoxy resin have been investigated by differential scanning calorimetry (DSC), FT-IR, and dynamic mechanical analysis (DMA). The thermal and mechanical properties were characterized by thermogravimetric analysis (TGA), thermomechanical analysis (TMA), flexural, impact strength, and the critical stress intensity factor tests. The results showed that a large number of physical crosslinks formed by intermolecular and intramolecular hydrogen bonding indeed existed in the TGDDM/F-51/PPENK blends. These interactions gave good compatibility between PPENK and epoxy resin. So that any phase separation had not been detected by DMA and scanning electron microscope (SEM). Beyond that the interaction could also be a benefit to the thermal and mechanical properties. Compared with the neat epoxy resin, the critical stress intensity factor values reached the maximum at 10-phr PPENK, as well as the impact strength. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 42938.

Synthesis, curing and properties of poly(phthalazione ether sulfone ketone) copolymers crosslinked by click chemistry

Co-reporter:Qin-zheng He;Jin-yan Wang 王锦艳;Lei Song;Xi-gao Jian

Chinese Journal of Polymer Science 2016 Volume 34( Issue 10) pp:1208-1219

Publication Date(Web):2016 October

DOI:10.1007/s10118-016-1835-z

Functionalized poly(phthalazinone ether sulfone ketone) was synthesized by successive chloromethylation and azidation, followed by curing reaction with the propargyl end-groups of various molecular weight crosslinking agents in the presence of Cu(I) catalyst via the azide-alkyne click reaction. The influences of the chain length of crosslinking agents on the poly(phthalazinone ether sulfone ketone) system were studied. FTIR and DSC tests demonstrated certain crosslinking by azide-alkyne reaction with the formation of triazole ring. DSC results showed that curing temperature shifted to lower temperatures considerably in the presence of Cu(I) catalyst. TGA showed cured polymers were of much higher thermal stability, including higher thermal decomposition temperatures and higher char-yielding properties. After being cured, the polymers became insoluble in organic solvents and the gel fraction of the cured polymers exceeded 71%. Wide-angle X-ray diffraction results indicated there was a short distance order in the poly(ether sulfone) (PES) main chain except for the azido methyl poly(phthalazinone ether sulfone ketone) and 4,4’ -bis(2-propynyloxy) biphenyl ( AMPPESK-BP) system.

Construction of donor-acceptor polymers containing thiophene-phthalazinone moiety via classic Ullmann CN coupling polymerization and their optical-electrical properties

Co-reporter:Jianhua Han, Haoyue Yin, Cheng Liu, Jinyan Wang, Xigao Jian

Polymer 2016 Volume 101() pp:241-256

Publication Date(Web):28 September 2016

DOI:10.1016/j.polymer.2016.08.090

•The copper catalyzed classic Ullmann CN coupling polymerization was investigated through the model reactions.•Three phthalazinone-based monomers were polymerized with three thiophene-based monomers via Ullmann polymerization.•The molecular weights of synthesized polymers are in range of 6.4- 34.6 kDa with PDI between 1.54 and 3.18.•These nine donor-acceptor polymers show strong UV–Vis–NIR absorption manners and emission color from blue to red regions.The copper catalyzed Ullmann polymerization is rarely used in polymer chemistry filed owing to the covered mechanism and insufficient conversion. Herein, we present the development of an efficient Ullmann CN coupling polymerization route to synthesize conjugated Donor-Acceptor (D-A) polymers containing thiophene-phthalazinone moiety. The model reactions were carried out to investigate varies solvents, bases, catalytic systems and substrate reactivity effects on the Ullmann CN coupling reactions. We demonstrate that the reaction conversion is highly depended on the substrate reactivity. By designing rational structures of thiophene-based di-bromo monomers, the molecular weights of polymers synthesized by classic Ullmann CN coupling polymerization are high, in range of 6.4–34.6 kDa (PDI = 1.54–3.18) with 77–98% yields. Benefiting from the D-A conjugated effect of thiophene-phthalazinone moiety, the optoelectronics properties were studied and these nine polymers show strong UV–Vis–NIR absorption manners and emission color from blue to red regions. Overall, given the discussions and results in this work offer a new perspective for classic Ullmann CN coupling polymerization to synthesize high molecular weight polymers as promising candidates for photoelectric materials.We present an efficient Ullmann CN coupling polymerization route to synthesize conjugated donor-acceptor polymers containing thiophene-phthalazinone moiety with strong UV–Vis–NIR absorption manners and emission color from blue to red regions.

Synthesis, characterization and thermal decomposition of novel soluble copoly(aryl ether nitrile) containing phthalazinone and biphenyl moieties

Co-reporter:Rui Liu;Cheng Liu;Jinlong Li;Xigao Jian

Polymer Bulletin 2016 Volume 73( Issue 7) pp:1811-1826

Publication Date(Web):2016 July

DOI:10.1007/s00289-015-1578-y

A series of novel soluble phthalazinone-based copoly(aryl ether nitrile)s (PPBENs) were successfully synthesized by the nucleophilic substitution reaction of 2,6-difluorobenzonitrile (DFBN) with varying mole proportions of 4-(4-hydroxylphenyl)-2,3-phthalazin-1(2H)-one (DHPZ) and 4,4′-dihydroxybiphenyl (BP). These obtained copolymers had inherent viscosities between 0.88 and 1.26 dL/g in N-methyl-2-pyrrolidone (NMP) at a concentration of 0.5 g dL−1 at 25 °C. Most of the obtained copolymers were soluble in common polar aprotic solvents, involving NMP, DMF, DMAc and chloroform, etc., at room temperature. The glass transition temperature was found to increase with increasing the DHPZ unit concentration in the copolymer main chain, ranging from 222 to 286 °C. Thermal gravimetric analysis showed that all the copolymers had 5 % weight loss temperature up to 521 °C and the high char yield above 65 % at 800 °C in nitrogen atmosphere. PPBEN2 exhibited the best mechanical properties which were measured using film samples. Its tensile strength and elongation at break were up to 137 MPa and 15 %, respectively. The thermal degradation process of PPBENs was discussed using thermogravimetric analysis (TGA) and FTIR. The apparent activation energy values were 273.5 and 274.1 kJ/mol which were calculated by Kissinger–Akahira–Sunose method and Flynn–Wall–Ozawa method, respectively. The results showed that the obtained copolymers possess excellent thermooxidation.

Temperature for curing phthalonitrile-terminated poly(phthalazinone ether nitrile) reduced by a mixed curing agent and its curing behavior

Co-reporter:Zhihuan Weng, Jiayi Fu, Lishuai Zong, Cheng Liu, Jinyan Wang and Xigao Jian

RSC Advances 2015 vol. 5(Issue 112) pp:92055-92060

Publication Date(Web):12 Oct 2015

DOI:10.1039/C5RA17234A

A mixture of ammonium molybdate tetrahydrate and urea (AMTU) was developed successfully to catalyze phthalonitrile to afford 2,4,6-tris(2-cyanophenyl)-1,3,5-triazine. Then AMTU was employed as a curing agent to promote the curing reaction of phthalonitrile-terminated poly(phthalazinone ether nitrile) (PPEN-Ph), and the effect of the novel curing agent was studied by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The initial curing temperature and apparent activation energy Ea (based on the Kissinger equation) were reduced from 268.5 °C and 201.5 kJ mol−1 using the common curing agent ZnCl2, to 223.0 °C and 78.4 kJ mol−1 using AMTU, respectively, under identical curing conditions. Moreover, the resulting thermosetting resin over AMTU showed excellent thermal stability; the Td5% and Td10% were 487 °C and 540 °C, respectively, and the char residue was up to 75% at 800 °C. These results indicated that AMTU could reduce the curing temperature for PPEN-Ph effectively, and it may be a good candidate as a curing agent for phthalonitrile resins.

Thermally stable phthalonitrile resins based on multiple oligo (aryl ether)s with phenyl-s-triazine moieties in backbones

Co-reporter:Lishuai Zong, Cheng Liu, Yujie Guo, Jinyan Wang and Xigao Jian

RSC Advances 2015 vol. 5(Issue 94) pp:77027-77036

Publication Date(Web):24 Aug 2015

DOI:10.1039/C5RA12637A

Many efforts have been devoted to tailoring the architecture of phthalonitrile (PN) polymers in recent years. Herein, we disclose a series of novel PN oligomers (PBP-Phs) bearing heteroaromatic phenyl-s-triazine moieties, serving as thermally stable segments in the polymer backbones. With bis(4-[4-aminophenoxy]phenyl)sulfone as a curing additive, PBP-Phs displayed commendable processability. After curing at high temperatures (up to 375 °C), the resulting networks (Th-PBPs) exhibited high glass transition temperatures ranging from 294 °C to 400 °C and outstanding thermal stability with a weight retention of 95% in N2 lying between 538 °C and 582 °C; the overall thermal properties were closely connected with the oligomer molar weights. Additionally, the feasibility of producing Th-PBPs reinforced with unidirectional continuous carbon fibers (CF) was evaluated. The results show that CF/Th-PBP laminates possess high flexural strength (1339–1855 MPa) and interlaminar shear strength (71.8–92.2 MPa).

Preparation and characterization of electrospun poly(phthalazinone ether nitrile ketone) membrane with novel thermally stable properties

Co-reporter:Gang Wang, Hao Zhang, Bingqing Qian, Jinyan Wang, Xigao Jian, Jieshan Qiu

Applied Surface Science 2015 Volume 351() pp:169-174

Publication Date(Web):1 October 2015

DOI:10.1016/j.apsusc.2015.05.124

Highlights

•: Poly (phthalazinone ether nitrile ketone) (PPENK) was used to successfully prepare nanofiber membranes by electrospinning.
•: Electrospun membrane exhibits a good thermostability.
•: Electrospun membrane.

Donor–acceptor copolymers containing the phthalazinone–thiophene structure synthesized by classical nucleophilic aromatic polymerization

Co-reporter:Jianhua Han, Kuanyu Yuan, Cheng Liu, Jinyan Wang and Xigao Jian

RSC Advances 2015 vol. 5(Issue 39) pp:30445-30455

Publication Date(Web):13 Mar 2015

DOI:10.1039/C5RA03771A

A series of new donor–acceptor copolymers based on a novel monomer containing phthalazinone and thiophene structures, were synthesized by classical nucleophilic displacement step polymerization reaction, and then were fully characterized. Their thermal, optical, electrochemical properties and quantum chemical calculations were investigated in detail. The comparisons between the linkage of ketone/di-ketone/sulfone groups and phenyl/naphthalene groups in the resulting polymer backbone were carried out to explore the relationship of the structure and the properties in the polymer system. The number average molecular weights of the resulting copolymers are 15 kDa–24 kDa. All of the copolymers are stable up to 441 °C, and their 5% weight loss temperatures are higher than 489 °C. Their optical band gap and HOMO energy levels vary from 2.36 eV to 2.76 eV and −5.16 eV to −5.51 eV, respectively. The soluble copolymers obtained exhibit blue-fluorescence. Their photoluminescence quantum yield ranges from 0.04 to 0.28 in N-methyl-2-pyrrolidone. These non-ether bond polymers may be potential candidates in photoelectric application.

Soluble and crosslinkable poly(phthalazinone ether ketone)s with pendent terminal ethynyl groups: synthesis, characterization and click modification

Co-reporter:QinZheng He;LiShuai Zong;Rui Liu ;XiGao Jian

Polymer International 2015 Volume 64( Issue 7) pp:875-883

Publication Date(Web):

DOI:10.1002/pi.4860

Abstract

New poly(phthalazinone ether ketone)s (PPEKs) with pendent terminal ethynyl groups were synthesized by the aromatic nucleophilic substitution (S_NAr) polycondensation reaction of a new bisphenol monomer, 2-(3-ethynylphenyl)hydroquinone, with 4-(4′-hydroxyphenyl)phthalazin-1(2H)-one and 4,4′-bis(4-fluorophenyl) ketone, followed by click modification reaction with 1-azidopyrene. Fourier transform infrared and NMR spectral data of the model compound indicated that the terminal ethynyl groups were stable in S_NAr reaction conditions, thus allowing the synthesis of the desired polymers. The PPEKs obtained with glass transition temperature (T_g) in the range 152–245 °C were amorphous, characterized by wide-angle X-ray diffraction, and dissolved in organic solvent to cast into transparent and flexible films. Differential scanning calorimetry results indicated that the curing reaction of the terminal ethynyl groups of the copolymers took place upon heating to 250 °C. The T_g of cured PPEKs was increased to about 260 °C. They also exhibited excellent thermal stability with 5% weight loss temperatures ranging from 448 to 527 °C in various atmospheres. The PPEKs with pendent terminal ethynyl groups were subsequently functionalized with pyrene through click reaction. A dilute chloroform solution displayed a red-shifted emission profile. © 2014 Society of Chemical Industry

An investigation of epoxy/thermoplastic blends based on addition of a novel copoly(aryl ether nitrile) containing phthalazinone and biphenyl moieties

Co-reporter:Rui Liu;Jinlong Li ;Xigao Jian

Polymer International 2015 Volume 64( Issue 12) pp:1786-1793

Publication Date(Web):

DOI:10.1002/pi.4980

Abstract

In this paper, a novel soluble copoly(aryl ether nitrile) containing phthalazinone and biphenyl moieties (PPBEN) was synthesized for the first time to improve the impact resistance of tetraglycidyl 4,4'-diaminodiphenylmethane epoxy resin cured with 4,4-diaminodiphenylsulfone. Then a series of blends were prepared via solution blending with different contents of PPBEN. The thermal and mechanical properties and the micromorphology of the cured blends were investigated by differential scanning calorimetry, dynamic mechanical analysis (DMA), parallel plate rheometry, mechanical property tests and SEM analysis, respectively. The results indicated that the incorporation of thermoplastic PPBEN delayed the epoxy curing reaction, and the crosslinking density of epoxies was also reduced. The no-notch impact strength of the cured blend with 15% PPBEN was up to 16.7 kJ m⁻², higher by about 104% than that of pure epoxy resin without sacrificing the modulus due to a specific sea-island structure. All the blends showed two-phase morphology characterized by DMA and SEM. The size of the thermoplastic morphology was only 70−80 nm, much less than that of commonly used thermoplastics, due to the special segment structure of PPBEN. © 2015 Society of Chemical Industry

Enhanced thermal properties of phthalonitrile networks by cooperating phenyl-s-triazine moieties in backbones

Co-reporter:Lishuai Zong, Cheng Liu, Shouhai Zhang, Jinyan Wang, Xigao Jian

Polymer 2015 Volume 77() pp:177-188

Publication Date(Web):23 October 2015

DOI:10.1016/j.polymer.2015.09.035

•The s-triazine-containing monomer was facilely prepared via a one-step approach.•This type of phthalonitrile could be readily processed with addition of diamine 6.•The Tg of the was significantly improved at around 400 °C.•The cured 7s have exhibited outstanding thermal and thermal-oxidative stabilities.•The 7/CF laminate possessed high flexxural strength and interlaminar shear strength.The development of phthalonitrile resins is of particular interest for aerospace applications because of their excellent heat resistance. Here, heteroaromatic phenyl-s-triazine moieties have been introduced into the architecture of the phthalonitrile resin as thermally stable segments via a two-step, one-pot reaction. Bis(4-[4-aminophenoxy]phenyl)sulfone was selected to promote the curing reaction, and the gelation time could be readily controlled by the diamine concentration and the curing temperature as evidenced by rheometric measurements. The curing procedure was optimized to give high cross-linking density networks. The resulting networks exhibit high glass transition temperatures at around 400 °C, outstanding thermo-oxidative stability with weight retention of 95% ranging from 539 °C to 552 °C, suggesting an improvement of the thermal properties imposed by phenyl-s-triazine units. Additionally, the CF laminate of the resin possesses high flexural strength of 1722 MPa and interlaminar shear strength of 71 MPa at ambient temperature, and these values retain 255 MPa and 36 MPa at 450 °C, respectively.Phenyl-s-triazine units in backbones would endow phthalonitrile networks enhanced thermal properties. Such phthalonitrile resins could be readily processed for preparing their carbon fiber reinforced composites.

Soluble and thermally stable copoly(phenyl-s-triazine)s containing both diphenylfluorene and phthalazinone units in the backbone

Co-reporter:Lishuai Zong;Cheng Liu;Rui Liu;Xigao Jian

Polymer Bulletin 2014 Volume 71( Issue 10) pp:2641-2660

Publication Date(Web):2014 October

DOI:10.1007/s00289-014-1216-0

A series of novel copoly(phenyl-s-triazine)s were prepared by solution polycondensation of 2,4-bis(4-fluorophenyl)-6-phenyl-1,3,5-s-triazine (BFPT) with 9,9-bis(4-hydroxyphenyl)fluorine (BHF) and 4-(4-hydroxylphenyl)(2H)-phthalazin-1-one (HHPZ) to investigate the effects of bulky diphenylfluorene units on solubility as well as thermal and mechanical properties. The synthetic procedure was efficiently optimized, resulting in high Mn up to 4.3 × 104 g/mol in GPC. Moreover, the introduction of diphenylfluorene moieties in the main chains leads to the outstanding modification in the solubility of the copolymers in common organic solvents, such as chloroform, chlorobenzene (CB) and N-methylpyrrolidone (NMP). Simultaneously, the copolymers exhibit remarkable dimensional stability as evidenced by DMA, and maintain excellent thermal properties with glass transition temperatures (Tgs) ranging from 307 to 340 °C, 5 % mass-loss temperatures lying between 525 and 551 °C, and char yields at 800 °C higher than 55 % in N2. Their solubility increases with the increase of diphenylfluorene content in the polymer backbone, and the thermal properties just decrease slightly. The films obtained via solution casting technology possess commendable mechanical properties, even at elevated temperatures.