Synthesis and characterization of novel benzoxazines containing nitrile and allyl groups and their polymers

e-Polymers ◽  
2010 ◽  
Vol 10 (1) ◽  
Author(s):  
Hongchun Zhang ◽  
Zaijun Lu
Keyword(s):  
Thermal Stability ◽  
Glass Transition ◽  
Thermal Properties ◽  
Transition Temperature ◽  
Ring Opening ◽  
Synthesis And Characterization ◽  
Curing Process ◽  
Oxazine Ring ◽  
Thermal Stability Of

AbstractA p-cyanophenol and allylamine based benzoxazine has been synthesized and characterized. This benzoxazine has nitrile and allyl functionalities that can polymerize, resulting in a highly crosslinked material. The DSC spectra of novel benzoxazine monomer reveal that incorporation of the nitrile and allyl group greatly decreases the ring-opening temperature of oxazine rings (140°C). The IR spectra of curing process indicate that the polymerization of oxazine ring accompany with the curing reaction of allyl and nitrile groups. Benzoxazine monomers with one or none of the two functionalities were also prepared to study structure effect on thermal properties of resulted polymer. The comparison of results confirms that introducing the two functionalities improved glass transition temperature (238 °C), thermal stability of polybenzoxazine (T5%=340 °C), and char yield (57%).

scholarly journals The Influence of Substituents in Phosphazene Catalyst-Flame Retardant on the Thermochemistry of Benzoxazine Curing

Polymers ◽  
2021 ◽  
Vol 13 (18) ◽  
pp. 3111
Author(s):  
Natalia V. Bornosuz ◽  
Roman F. Korotkov ◽  
Alexander A. Kolenchenko ◽  
Alexey V. Shapagin ◽  
Alexey V. Orlov ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Catalytic Activity ◽  
Glass Transition ◽  
Thermal Properties ◽  
Transition Temperature ◽  
Curing Process ◽  
Flame Resistance ◽  
Dispersion Phase ◽  
Thermal Stability Of ◽  
Influence Of Substituents

This work is devoted to the influence of phosphazene modifiers with different substituents on the curing process, thermal properties and flammability of benzoxazine resin. Novel catalysts with m-toluidine substituents were introduced. The catalytic activity of studied phosphazene compounds decreased in the row: hexachlorocyclotriphosphazene (HCP) > tetra m-toluidine substituted phosphazene PN-mt (4) > hexa m-toluidine substituted phosphazene PN-mt (6) > hexaphenoxycyclotriphosphazene (HPP), where HPP is totally inactive. Two types of catalysis: basic and acid were proposed. A brief study of resulting properties of polybenzoxazines was presented. The addition of any studied modifier caused the decrease of glass transition temperature and thermal stability of polymers. The morphology of cured compositions was characterized by matrix-dispersion phase structure. All phosphazene containing polybenzoxazines demonstrated the improved flame resistance.

Synthesis and characterization of extended poly(phenylquinoxalines) containing carbonyl, ether and sulphide linking groups

1995 ◽  
Vol 7 (4) ◽  
pp. 481-492 ◽  
Author(s):  
Rajendra K Singh ◽  
Rooma Mago Mehta ◽  
R G Bass
Keyword(s):  
Thermal Stability ◽  
Weight Loss ◽  
Glass Transition ◽  
Transition Temperature ◽  
Primary Objective ◽  
Synthesis And Characterization ◽  
Glass Transition Temperatures ◽  
Hydrocarbon Solvents ◽  
As Solubility

A series of eight novel extended poly(phenylquinoxalines) (PPQs) containing carbonyl, ether and sulphide linking groups were prepared by polycondensation of 4,4'-bis(phenylglyoxalyl-4-phenoxy-4'-benzoyl)diphenyl sulphide, I-D, and 4,4'-bis(phenyl glyoxalyl-4-phenylthio-4'-benzoyl)diphenyl sulphide, 2-D, with four aromatic bis(o-diamines) in m-cresol. The primary objective of this study was to correlate the effect of these linkages on the various properties such as solubility, thermal stability and glass transition temperature of the PPQs. Polymerization of 1-D was carried out in an oil bath maintained at 195-200C whereas polymerization of 2-D was performed at ambient temperature. The polymers prepared were soluble in m-cresol. dimethylsulphoxide, N,N-dimethylacetamide, I-methyl-2-pyrrolidinone and chlorinated hydrocarbon solvents, and formed tough transparent, yellow fingernail-creasable films from chloroform solutions. The inherent viscosities ranged between 0.44 and 0.96 dl g' '. The glass transition temperatures were nearly identical for both systems and ranged from 217-231 'C for polymers prepared from l-D and from 215-233"C for polymers prepared from 2-D. The PPQs having carbonyl and stJlphide linking groups had higher thermal stability in comparison to PPQs having carbonyl, ether and sulphide linkages. The temperature of 10% weight loss for I-D ranged from 484-496 'C in air and 485-516"C in helium whereas those for 2-D ranged from 538-579 XC in air and 522-549 in helium.

Thermal Properties of Acrylic Resin Denture Base Material Containing Silver Nanoparticle Synthesized from Aqueous Extract of Boesenbergia rotunda

2018 ◽  
Vol 777 ◽  
pp. 173-177
Author(s):  
Panjaporn Wongwitthayakool ◽  
Matsayapan Pudla
Keyword(s):  
Thermal Stability ◽  
Glass Transition ◽  
Thermal Properties ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Base Material ◽  
Acrylic Resin ◽  
Denture Base ◽  
Acrylic Resins ◽  
Thermal Stability Of

Silver nanoparticles (AgNPs) were synthesized by bioreduction method using aqueous extracts of Boesenbergia rotunda as reducing and stabilizing agents. Ultraviolet-Visible (UV-Vis) spectrophotometer was utilized to monitor the qualitative formation of AgNPs. The UV-Vis spectrum showed that the spherical AgNPs with diameter of 20-40 nm were formed. The antifugal activity of synthesized AgNPs was investigated using Candida albicans, which was found that the synthesized AgNPs could be used as effective growth inhibitors. The influence of the incorporation of prepared AgNPs on thermal properties of the acrylic denture base material was investigated. Glass transition temperature of filled acrylic resins was studied using the dynamic mechanical analyzer (DMA). The temperature sweeps were performed with tension mode. Thermogravimetry analysis (TGA) was used to examine effect of AgNP concentration and thermocycling (1250, 2500, 5000, and 10000 cycles) on thermal stability of AgNP filled acrylic resin denture base materials. Glass transition temperature (Tg) of the acrylic resins slightly increase with increasing AgNP contents. TGA results indicated that AgNP retarded thermal degradation of acrylic resin denture material, and thermocycling did not affect thermal stability of AgNP filled acrylic resin denture material.

Effects of graphene on thermal properties and thermal stability of polycarbonate/graphene nanocomposite

2021 ◽  
pp. 089270572199788
Author(s):  
Md Amir Sohel ◽  
Abhijit Mondal ◽  
P Mohammad Arif ◽  
Sabu Thomas ◽  
Asmita SenGupta
Keyword(s):  
Thermal Stability ◽  
Thermal Decomposition ◽  
Glass Transition ◽  
Thermal Properties ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Multilayer Graphene ◽  
Melt Mixing ◽  
Graphene Nanocomposite ◽  
Thermal Stability Of

Polycarbonate (PC) /graphene nanocomposite was prepared using multilayer graphene (MLG) with loadings of 0.5, 1, and 3 wt% via melt mixing process. Morphological, structural, and thermal properties of the PC/MLG nanocomposites are investigated to look into the influence of MLG on the nanocomposite. A significant increase (∼6.4°C) in glass transition temperature is observed upon the addition of 3 wt% of MLG into the polycarbonate matrix. This increase in glass transition temperature may be due to the interaction between the MLG and polycarbonate polymer matrix. The specific heat capacity of pure PC and PC/MLG nanocomposites varies linearly with temperature below their glass transition. Upon the addition of MLGs, the overall thermal stability of PC/MLG nanocomposites increases with MLG loadings. A maximum increase about 29.23°C in T onset of thermal decomposition is observed in PC/MLG nanocomposite having 3 wt% of MLG loading. The activation energy ( Ea) of thermal decomposition is also calculated by kinetic analysis of thermal decomposition of the PC/MLG nanocomposites using Horowitz–Metzger and Broido’s methods.

Synthesis and Characterization of Novel Polyfluorene Derivatives

2013 ◽  
Vol 815 ◽  
pp. 443-447
Author(s):  
Li Di Zhou ◽  
Xiao Dan Hu ◽  
Shao Hong Wang ◽  
Zhao Xia Hou ◽  
Mei Han Wang
Keyword(s):  
Glass Transition ◽  
Thermal Properties ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Solid State ◽  
Coupling Reaction ◽  
Synthesis And Characterization ◽  
Sonogashira Coupling ◽  
Sonogashira Coupling Reaction

A novel series of copolymers containing fluorene units are synthesized by Sonogashira coupling reaction in mild condition. Benzene, naphthalene and anthracene are co-polymerized with ethynylfluorene, respectively. The structures are confirmed by NMR, Mass, Elemental analysis and GPC. The polymers have good thermal properties with glass-transition temperature of 90-155°C(Tg), and they have bandgaps from 2.21-2.77 eV. The results of photoluminescence in solid state show that introduction of huge chromophore could effectively suppress the formation of aggregates and excimers which typically cause red-shifted or new emission.

scholarly journals Synthesis and characterization of poly(butylene terephthalate) copolyesters derived from threitol

2021 ◽  
pp. 096739112110232
Author(s):  
N Ittobane ◽  
A Martínez de Ilarduya ◽  
A Alla ◽  
S Muñoz-Guerra
Keyword(s):  
Crystal Structure ◽  
Glass Transition ◽  
Thermal Properties ◽  
Transition Temperature ◽  
Synthesis And Characterization ◽  
Terephthaloyl Chloride ◽  
Butylene Terephthalate ◽  
Molecular Weights ◽  
Random Microstructure

The synthesis, characterization, and thermal properties of partially renewable poly(butylene terephthalate) copolyesters containing alditol units are described. These copolyesters were obtained by polycondensation in solution from mixtures of 1,4-butanediol and 2,3-di- O-benzyl-L-threitol with terephthaloyl chloride. Copolyesters with weight-average molecular weights oscillating between 4 000 and 12 000 g·mol−1 and dispersities around 1.5 were obtained. All them had a random microstructure and were thermally stable well above 300°C. Copolyesters containing up to 30% of dibenzyl threitol units were found to be crystalline and to adopt the same crystal structure as the parent homopolyester poly(butylene terephthalate). The melting temperature and crystallinity were observed to decrease, and the glass transition temperature to increase, with increasing amounts of alditol units incorporated in the copolyester. Furthermore, the crystallizability was depressed by copolymerization.

Novel Copolymers of N-[(4-bromo-3,5- difluorine) phenyl] acryl- amide with Methyl Methacrylate: Synthesis, Characterization and Thermal Properties

2013 ◽  
Vol 750-752 ◽  
pp. 1125-1129
Author(s):  
Xin Ding Yao ◽  
Rui Na Fang ◽  
Hong Jian Pang ◽  
Zong Wu Wang ◽  
Guo Ji Liu
Keyword(s):  
Thermal Stability ◽  
Glass Transition ◽  
Thermal Properties ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Thermogravimetric Analysis ◽  
Methyl Methacrylate ◽  
1H Nmr ◽  
Nmr Spectra ◽  
Thermal Stability Of

Copolymers of N-[(4-bromo-3,5-difluorine) phenyacrylamide (BDPA), with methyl methacrylate (MMA) were synthesized in N,N-Dimethylformamide at 75±1°C using 2,2-azobisisobutyronitrile (AIBN) as an initiator with different monomer-to-monomer ratios in the feed. The copolymers were characterized by FTIR and 1H NMR spectra. The glass transition temperature of the copolymers decreases with increase in BDPA content. The thermogravimetric analysis of the polymers showed that the thermal stability of the copolymer decreases with BDPA content.

scholarly journals Synthesis and Characterization of Semicrystalline Polyimides Containing Bridged Linkages

2018 ◽  
Vol 2018 ◽  
pp. 1-7 ◽  
Author(s):  
Min Chao
Keyword(s):  
Thermal Stability ◽  
Weight Loss ◽  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
High Weight ◽  
Softening Temperature ◽  
Synthesis And Characterization ◽  
Excellent Thermal Stability

A series of polyimides (PI) containing bridged linkages were prepared successfully through a three-step technique. The results indicated that the glass transition temperature (Tg) of polyimides was affected by flexibility of polymer chain and the intermolecular interactions. ODPA-TPER-based polyimide possesses the lowest Tg, which was 214°C. All polyimides had semicrystalline characteristics, and ODPA-TPER-based PI exhibited the lowest melting temperature (Tm) at 316°C. The polyimides had high weight loss temperatures, which indicated that bridged linkages can reduce the softening temperature, meanwhile keeping excellent thermal stability.

Synthesis and Characterization of Acrylamide Based Benzoxazine

2012 ◽  
Vol 621 ◽  
pp. 11-16
Author(s):  
Erigene Bakangura ◽  
Zhong Yu Luo ◽  
Guang Kai Wang ◽  
Yang Bin ◽  
Yan Ping Yue ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Phenolic Resin ◽  
Curing Temperature ◽  
Hydroxyl Group ◽  
Synthesis And Characterization ◽  
Oxazine Ring ◽  
Ft Ir ◽  
Thermal Stability Of ◽  
Direct Condensation

Novel benzoxazine monomers, acrylamide based benzoxazine, have been prepared from direct condensation of phenols with acrylamide and formaldehyde. 1H NMR and FT-IR, DSC and TGA were used to analysis the structure, compositions and investigate the curing behaviour and thermal stability, respectively. Solvent effects were studied. Solventless method is good for higher formation ratio of benzoxazine to the corresponding phenolic resin. The ratio for P-AA is 36.4% by solventless method, while it’s about 26% by toluene solvent; and 44% and 20% for B-AA, respectively. The monomers mixtures exhibit curing temperature (ca.187oC) without catalysts lower than their related allyl-benzoxazine. The FT-IR of different curing temperature shows the disappearance of double bond absorption at 1668 cm-1 and oxazine ring at 1232 cm-1 and appearance of hydroxyl group at 3446 cm-1. Thermal stability of cured benzoxazine show good char residues compared with traditional benzoxazine of aniline.

Study of thermal behavior of poly (lactic) acid composites with electron beam irradiated luffa fiber

2020 ◽  
pp. 2150009
Author(s):  
S. Patra ◽  
K. L. Mohanta ◽  
C. Parida
Keyword(s):  
Thermal Stability ◽  
Electron Beam ◽  
Lactic Acid ◽  
Glass Transition ◽  
Thermal Properties ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Irradiation Dose ◽  
Poly Lactic Acid ◽  
Thermal Stability Of

Modification of surface of natural fibers by high energy electron beam irradiation (6 MeV) is a process for enhancing the adhesion between fiber and matrix. Composites reinforced with natural fiber have gained a prominent place in the field of research and innovation due to the advantages such as low cost, light weight and environment friendly factors. We have studied the thermal properties such as thermal degradation and crystallinity behavior of biodegradable composites using biodegradable polymer poly (lactic) acid (PLA) and fiber of luffa cylindrica (LC) fabricated by using injection molding technique. First, reinforcement LC fibers are irradiated with electron beam of 0.5, 1.0, 2.0, 4.0 and 10.0 Gy using 6 MeV linear accelerator at room temperature in presence of air. The thermal properties like glass transition temperature [Formula: see text], cold crystallization temperature [Formula: see text], melting peak temperature [Formula: see text] and thermal stability of the composites are studied using differential scanning calorimetry (DSC) in the temperature range from 30[Formula: see text]C to 250[Formula: see text]C and thermogravimetric analysis (TGA) in temperature range from 20[Formula: see text]C to 700[Formula: see text]C. The variation of these properties in response to the irradiation dose is analyzed in detail. It is observed that with increase in irradiation dose, glass transition temperature and crystallization temperature increase. However, the thermal stability of the composites is found to increase with increase in irradiation dose.

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