Polybenzoxazine Resins with Cellulose Phosphide: Preparation, Flame Retardancy and Mechanisms

Phosphated cellulose (PCF) was synthesized based on urea, phosphated acid and cellulose. The structure of the PCF was confirmed by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy coupled with the Energy Dispersive Spectrometer (SEM-EDS). Benzoxazine (Ba)/PCF hybrid materials were fabricated and thermally cured to prepare polybenzoxazine composites (PBa/PCF). The effects of PCF on the curing temperature of Ba were analyzed through differential scanning calorimetry (DSC). The thermogravimetric (TGA) results demonstrated an increased char residue of 50% for the PBa composites incorporating PCF-5% compared with the pure PBa. The peak heat release rate (PHRR) and total heat release (THR) values of the PBa/PCF-5% composites clearly decreased by 58.1% and 16.5% compared to those of the pristine PBa. The smoke released from the PBa/PCF system significantly reduced with the loading of PCF. Moreover, the limited oxygen index (LOI) and vertical burning test level (UL-94) of PBa/PCF-5% reached up to 31 and V0. The flame retardant mechanism of the PCF in the PBa matrix was investigated TG-FTIR and char residues analysis. Finally, the dynamical mechanical analysis (DMA) results demonstrated that the Tg of the PBa/PCF composites was approximately 230 °C, which does not affect further applications of PBa composites.

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Synthesis and Characterization of Aluminum 2-Carboxyethyl-Phenyl-Phosphinate and Its Flame-Retardant Application in Polyester

Polymers ◽

10.3390/polym11121969 ◽

2019 ◽

Vol 11 (12) ◽

pp. 1969 ◽

Cited By ~ 2

Author(s):

Zhongying Yao ◽

Xinxin Liu ◽

Lijun Qian ◽

Yajun Chen ◽

Bo Xu ◽

...

Keyword(s):

Heat Release ◽

Flame Retardant ◽

Gas Phase ◽

Oxygen Index ◽

Peak Heat Release Rate ◽

Flame Inhibition ◽

Polyester Textile ◽

Effective Heat Of Combustion ◽

Limited Oxygen

A flame retardant aluminum 2-carboxyethyl-phenyl-phosphinate (CPA-Al) was synthesized through the salification reaction. The molecular structure of CPA-Al and thermal stability were characterized by solid nuclear magnetic resonance, Fourier transform infrared spectroscopy, and thermogravimetric analysis. Subsequently, CPA-Al mixed in polyurethane was coated on polyester textile to obtain flame-retardant samples. The addition of 14.7 wt.% CPA-Al in textile sample can bring a limited oxygen index (LOI) value of 24.5%, 0 s after flame time, and the vertical burning B1 rating. Meanwhile, the incorporated CPA-Al reduced the peak heat release rate, total heat release, average effective heat of combustion, and increased the charring capacity of polyester textiles in contrast to the samples without CPA-Al. CPA-Al exerted not only its flame inhibition effect in gas phase, but also the charring and barrier effect in the condensed phase. Besides, with an increasing CPA-Al ratio in polyester textile, the contact angle gradually decreased from 123.6° to 75.6°, indicating that the surficial property of coating from hydrophobic to hydrophilic, thereby increasing the moisture permeability of polyester textile.

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Study of a Cu-Al-Mn Shape Memory Alloy Produced by Plasma Melting Followed by Injection Molding

MRS Proceedings ◽

10.1557/opl.2014.753 ◽

2014 ◽

Vol 1611 ◽

pp. 25-30

Author(s):

Francisco Fernando Roberto Pereira ◽

Maria Goretti Ferreira Coutinho ◽

Bruno Moura Miranda ◽

Carlos José de Araújo

Keyword(s):

Injection Molding ◽

Shape Memory ◽

Shape Recovery ◽

Permanent Deformation ◽

Melting Process ◽

Mechanical Analysis ◽

Scanning Calorimetry ◽

Dynamical Mechanical Analysis ◽

Plasma Melting ◽

New Applications

ABSTRACTShape Memory Alloys (SMA) are characterized by the capacity to recover a permanent deformation after being heated above a critical temperature called Final Austenite Temperature (Af). The Ni-Ti SMA are the most commercially used, however recent studies showed that the Cu-Al-Mn SMA present significant shape recovery and mechanical properties, showing a strong potential for developing new applications. In this context, the main goal of this work is to manufacture a Cu-Al-Mn SMA through a plasma melting process followed by injection molding of liquid metal and then characterize the samples, using the following techniques: Optical Microscopy (OM), Differential Scanning Calorimetry (DSC), Electrical Resistance as a function of Temperature (ERT) tests, Dynamical Mechanical Analysis (DMA) and Microhardness (MH).

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Synthesis and properties of a novel high-temperature vinylpyridine-based phthalonitrile polymer

High Performance Polymers ◽

10.1177/0954008318801911 ◽

2018 ◽

Vol 31 (7) ◽

pp. 820-830 ◽

Cited By ~ 3

Author(s):

Haifeng Wang ◽

Zhenjiang Zhang ◽

Puguang Ji ◽

Xiaoyan Yu ◽

Kimiyoshi Naito ◽

...

Keyword(s):

Complex Viscosity ◽

Mechanical Analysis ◽

Curing Temperature ◽

Gravimetric Analysis ◽

Test Results ◽

Scanning Calorimetry ◽

Excellent Thermal Stability ◽

Rheological Analysis ◽

Dsc Analyses ◽

Low Complex

A novel vinylpyridine-based phthalonitrile monomer, 2,6-bis[3-(3,4-dicyanophenoxy)styryl]pyridine (BDSP), was resoundingly produced by a nucleophilic substitution reaction of 2,6-bis(3-hydroxystyryl)pyridine with 4-nitrophthalonitrile in the presence of potassium carbonate. The chemical structure of the synthesized BDSP was confirmed by proton (1H) and carbon (12C) nuclear magnetic resonance (NMR) as well as Fourier transform infrared (FTIR) analysis. The curing behavior of BDSP was investigated by FTIR and differential scanning calorimetry (DSC) analyses. The resin showed a low complex viscosity in the wide processing window between the monomer melting temperature and the curing temperature of the polymer, as discovered by rheological analysis. In addition, the properties of the polymer were studied by thermal gravimetric analysis (TGA) and dynamic mechanical analysis (DMA). Based on the test results, the BDSP polymer demonstrated superior processing performance, excellent thermal stability, outstanding mechanical properties, and low water uptake, and these advanced performance characteristics are critical to many fields.

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Block Copolymers of Poly(ω-Pentadecalactone) in Segmented Polyurethanes: Novel Biodegradable Shape Memory Polyurethanes

Polymers ◽

10.3390/polym12091928 ◽

2020 ◽

Vol 12 (9) ◽

pp. 1928

Author(s):

Katalin Czifrák ◽

Csilla Lakatos ◽

Marcell Árpád Kordován ◽

Lajos Nagy ◽

Lajos Daróczi ◽

...

Keyword(s):

Shape Memory ◽

Shape Recovery ◽

Mechanical Analysis ◽

Attenuated Total Reflectance ◽

Dibutyltin Dilaurate ◽

Scanning Calorimetry ◽

Dynamical Mechanical Analysis ◽

Good Shape ◽

Segmented Polyurethanes ◽

Shape Fixity

In this report, the synthesis of poly(ω-pentadecalactone) (PPDL) (co)polymers and their incorporation into polyurethanes (PUs) are reported. Optimal conditions for the ring-opening polymerization (ROP) of ω-pentadecalactone (PDL) using dibutyltin dilaurate catalyst were established. For the synthesis of linear and crosslinked PUs, 50 kDa poly(ε-caprolactone) (PCL) and 1,6-hexamethylenediisocyanate (HDI) were used. The obtained polyurethanes were characterized by Attenuated Total Reflectance Fourier-Transform Infrared spectroscopy (AT-FTIR), differential scanning calorimetry (DSC), and dynamical mechanical analysis (DMA). The DMA of the selected sample showed a rubbery plateau on the storage modulus versus temperature curve predicting shape memory behavior. Indeed, good shape memory performances were obtained with shape fixity (Rf) and shape recovery (Rr) ratios.

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Amino-Functionalized Lead Phthalocyanine-Modified Benzoxazine Resin: Curing Kinetics, Thermal, and Mechanical Properties

Polymers ◽

10.3390/polym11111855 ◽

2019 ◽

Vol 11 (11) ◽

pp. 1855 ◽

Cited By ~ 3

Author(s):

Li-wu Zu ◽

Bao-chang Gao ◽

Zhong-cheng Pan ◽

Jun Wang ◽

Abdul Qadeer Dayo ◽

...

Keyword(s):

Mechanical Properties ◽

Impact Strength ◽

Kinetic Parameters ◽

Curing Kinetics ◽

Dynamic Mechanical Properties ◽

Mechanical Analysis ◽

Curing Temperature ◽

Scanning Calorimetry ◽

Thermal Stabilities ◽

Dynamic Mechanical

Phenol-diaminodiphenylmethane-based benzoxazine (P-ddm)/phthalocyanine copolymer was prepared by using P-ddm resin as matrix and 3,10,17,24-tetra-aminoethoxy lead phthalocyanine (APbPc) as additive. Fourier-transform infrared (FTIR), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and thermogravimetric analysis (TGA) were used to investigate the curing behavior, curing kinetics, dynamic mechanical properties, thermal stability, and impact strength of the prepared copolymers. The kinetic parameters for the P-ddm/APbPc blend curing processes were examined by utilizing the iso-conversional, Flynn–Wall–Ozawa, and Málek methods. The P-ddm/APbPc blends exhibit two typical curing processes, and DSC results confirmed that the blending of APbPc monomer can effectively reduce the curing temperature of P-ddm resin. The autocatalytic models also described the non-isothermal curing reaction rate well, and the appropriate kinetic parameters of the curing process were obtained. The DMA and impact strength experiments proved that the blending of APbPc monomer can significantly improve the toughness and stiffness of P-ddm resin, the highest enhancements were observed on 25 wt.% addition of APbPc, the recorded values for the storage modulus and impact strength were 1003 MPa and 3.60 kJ/m2 higher, respectively, while a decline of 24.6 °C was observed in the glass transition temperature values. TGA curves indicated that the cured copolymers also exhibit excellent thermal stabilities.

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Synthesis of a Flame Retardant for Epoxy Resins: Thermal Stability, Flame Retardancy, and Flame-Retardant Modes

International Polymer Processing ◽

10.1515/ipp-2020-3915 ◽

2021 ◽

Vol 36 (2) ◽

pp. 172-184

Author(s):

Y. Zhang ◽

J. Liu ◽

S. Li

Keyword(s):

Infrared Spectroscopy ◽

Thermogravimetric Analysis ◽

Heat Release ◽

Flame Retardant ◽

Photoelectron Spectroscopy ◽

Epoxy Resins ◽

Oxygen Index ◽

Limited Oxygen Index ◽

Index Value ◽

Limited Oxygen

Abstract A polyphosphonate (PDPA) flame retardant that contains phenyl phosphonic dichloride and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide groups, has been synthesized. The flame retardant was introduced into epoxy resins (EP) and cured by 4,4’-diamino diphenylmethane. The vertical burning, limited-oxygen index and cone calorimeter tests reveal that the PDPA can enhance the flame-retardant properties of the EP significantly. With only a 4 wt% PDPA loading, the EP composites achieved a limited-oxygen index value of 33.4% and a V-0 rating in the vertical burning test, and the peak heat release rate and total heat release were decreased by 40.9% and 24.6%, respectively. The thermal properties and gas pyrolysis products of the EP composites were evaluated by thermogravimetric analysis and thermogravimetric analysis-Fourier transform infrared spectroscopy, and the morphology and structure of residual char were characterized by scanning electron microscopy, Flourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. To explain the combined effects of the condensed and gas phases, modes of the flame-retardant action are proposed.

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Gels from acrylic acid and hydroxypropyl cellulose via free radical polymerization

e-Polymers ◽

10.1515/epoly.2008.8.1.1697 ◽

2008 ◽

Vol 8 (1) ◽

Cited By ~ 2

Author(s):

Carlos F. Castro-Guerrero ◽

Ana Morales-Cepeda ◽

José Rivera-Armenta ◽

Ana Mendoza-Martínez ◽

Alberto Álvarez-Castillo

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Acrylic Acid ◽

Viscoelastic Properties ◽

Raw Materials ◽

Mechanical Analysis ◽

Hydroxypropyl Cellulose ◽

Scanning Calorimetry ◽

Dynamical Mechanical Analysis ◽

Scanning Electron

AbstractA hydrogel from acrylic acid and hydroxypropyl cellulose was made. The percentages of raw materials and crosslinkers were varied and its swelling behavior was evaluated. Some of the gels obtained absorbed more than 300% wt. The gels with higher swelling percentages were characterized by means of IR spectroscopy, differential scanning calorimetry (DSC), dynamical mechanical analysis (DMA), and scanning electron microscopy (SEM). The FTIR showed the presence of the main reactants in the gel, while the DSC showed a phase separation in the gel. This gel is partly biodegradable because of the content of hydroxypropyl cellulose and has the viscoelastic properties of poly(acrylic acid).

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Effect of Aromatic Petroleum Resin on Damping Properties of Polybutyl Methacrylate

Polymers ◽

10.3390/polym12030543 ◽

2020 ◽

Vol 12 (3) ◽

pp. 543

Author(s):

Songhan Wan ◽

Saisai Zhou ◽

Xing Huang ◽

Songbo Chen ◽

Shuwei Cai ◽

...

Keyword(s):

Mechanical Analysis ◽

Damping Properties ◽

Scanning Calorimetry ◽

Sem Images ◽

Dynamical Mechanical Analysis ◽

Petroleum Resin ◽

The Matrix ◽

Higher Temperature ◽

Dsc Curves ◽

Positive Effect

The damping properties of polybutyl methacrylate (PBMA)/aromatic petroleum resin (C9) composite were investigated in this work. In particular, a trace of styrene (St) was introduced to copolymerize with PBMA to improve the compatibility between C9 and matrix. The structure of the copolymer, P(BMA-co-St), was characterized by FTIR and 1HNMR. The P(BMA-co-St)/C9 composites were tested by differencial scanning calorimetry (DSC), scanning electron microscopy (SEM) and dynamical mechanical analysis (DMA). DSC curves of all P(BMA-co-1wt%St)/C9 composites expressed only one glass transition temperature (Tg). SEM images showed that C9 had good compatibility with the matrix after St was introduced. DMA curves indicated that the addition of C9 had a positive effect on the damping properties of PBMA. The loss tangent (tanδ) peak moved to a higher temperature with the increment content of C9, and the effective damping temperature range increased significantly. The influence of aromatic resin C9 and aliphatic resin (C5) on PBMA damping performance was compared. It was further shown that C9 with benzene ring effectively improved the damping performance of PBMA.

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Effects of chemical pre-treatment on structure and property of polyacrylonitrile based pre-oxidized fibers

Journal of Engineered Fibers and Fabrics ◽

10.1177/1558925019898946 ◽

2020 ◽

Vol 15 ◽

pp. 155892501989894

Author(s):

Xiaolu Sun ◽

Jiayin Song ◽

Jin Zhang ◽

Jingyan Liu ◽

Huizhen Ke ◽

...

Keyword(s):

Mechanical Properties ◽

Thermal Stability ◽

Heat Release ◽

Flame Retardant ◽

Oxygen Index ◽

Energy Dispersive Spectrometer ◽

Chemical Compositions ◽

Limiting Oxygen Index ◽

X Ray ◽

Pre Treatment

Polyacrylonitrile-based pre-oxidized fibers with improved thermal stability, flame retardant, and mechanical properties were made from the pristine polyacrylonitrile fibers through chemical pretreatment followed by pre-oxidation in air. The morphological structure of the polyacrylonitrile-based pre-oxidized fibers was investigated by Fourier transfer infrared spectra, X-ray diffraction, scanning electron microscopy, and X-ray energy dispersive spectrometer. The changes of characteristic functional groups and chemical compositions confirmed the successful modification of the polyacrylonitrile fibers during pre-treatment. The grooves and cracks on the surface of polyacrylonitrile-based pre-oxidized fibers were remarkably decreased in comparison with that of pristine polyacrylonitrile fibers. The evolution of crystalline structure of the polyacrylonitrile fibers proved the occurrence of cyclization reactions during pre-oxidation. Meanwhile, thermal stability, flame retardant, and mechanical properties of polyacrylonitrile-based pre-oxidized fibers were also investigated by thermogravimetric analyzer, oxygen index meter, micro combustion calorimeter, and single fiber tensile tester, respectively. The results demonstrated that the polyacrylonitrile-based pre-oxidized fibers initially pre-treated by hydroxylamine hydrochloride, followed by monoethanolamine, had a high limiting oxygen index of 40.1 and breaking strength of 2.03 cN/dtex. The peak of heat release rate and total heat release of polyacrylonitrile-based pre-oxidized fibers decreased significantly while its charred residues increased, contributing to the improved flame retardant property.

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Synthesis of a novel modified chitosan as an intumescent flame retardant for epoxy resin

e-Polymers ◽

10.1515/epoly-2020-0036 ◽

2020 ◽

Vol 20 (1) ◽

pp. 303-316

Author(s):

Haihua Yu ◽

Xiuhang Xu ◽

Yunfei Xia ◽

Mingzhen Pan ◽

Nighat Zarshad ◽

...

Keyword(s):

Heat Release ◽

Flame Retardant ◽

Epoxy Resin ◽

Oxygen Index ◽

Intumescent Flame Retardant ◽

Melamine Phosphate ◽

Modified Chitosan ◽

H Nmr ◽

New Type ◽

Limited Oxygen

AbstractAccording to the concept of fire life cycle assessment (LCA), a new type of intumescent flame retardant was designed and synthesized by chemically bonding chitosan, phosphorus pentoxide and melamine. The resultant compound, chitosan ethoxyl melamine phosphate (CEMP), was characterized by FTIR, 1H NMR, 31P NMR, XRD and SEM. The performance of CEMP and organic montmorillonite (OMMT) was evaluated in the substrate of epoxy resin (EP) with limited oxygen index (LOI), UL-94, cone calorimetric test (CCT), TGA and TG-IR. As a result, intumescent flame retardant EP (EP3) containing 30.6% LOI and V-0 rating was prepared by adding 3 wt% OMMT and 15 wt% CEMP. The CCT results indicated that CEMP and OMMT reduced the peak of heat release rate (PHRR) to about one fourth that of pure EP and total heat release (THR), 1/2. Decomposition of EP and EP3 was traced from 100 to 600°C by TG-IR.

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