Properties Of Bismaleimide Resin Research Articles

Construction of bismaleimide resin with enhanced flame retardancy and mechanical properties based on a novel DOPO-derived bismaleimide monomer

It’s known that the application of bismaleimide resins (BMI) is limited due to its brittleness and poor flame retardancy. A novel type of BMI monomer (MADQ) based on the typical phosphorus series flame retardant DOPO is designed to improve the fire safety of BMI. Besides, aliphatic long chain structure is introduced in MADQ, which is supposed to be conducive to reducing the rigidity of the BMI cross-linked network and thus to improve the toughness of BMI. It’s seen that with the incorporation of 5.24 wt% MADQ, the peak of heat release rate (PHRR) and total heat release (THR) of resultant BMI/MADQ-5 is reduced by 37.7% and 33.9%, respectively. Meanwhile, with modification of 1.07 wt% MADQ, BMI/MADQ-1 possesses UL-94V-0 rating. The relevant mechanism analysis reveals that the phosphaphenanthrene group in MADQ can exert flame retardancy effect both in condensed and gas phase. Besides, the impact strength of the BMI/MADQ is maximally increased by nearly 90.1%. Furthermore, the BMI/MADQ still maintains high tensile strength and thermal stability, which indicates the modification of MADQ did not deteriorate other properties of BMI. An innovative research idea and research basis for the preparation of intrinsic flame-retardant and toughened BMI is provided in this work.

Synthesis and properties of bismaleimide resins containing phthalide cardo and cyano groups

Two novel n ≈ 1 oligomeric bismaleimide monomers containing phthalide cardo and cyano groups (PCBMI and MCBMI) were designed and synthesized. The chemical structures of the monomers were confirmed from proton nuclear magnetic resonance spectroscopy and Fourier transform infrared spectroscopy. Both BMIs exhibit good solubility in common organic solvents, enabling easy solution processing. Thermal curing behaviors of the monomers were investigated by differential scanning calorimetry, displaying broad exothermic peaks and large thermal processing windows. Furthermore, PCBMI/carbon fiber composites were prepared, with their thermal stability and mechanical properties investigated. Thermogravimetric analysis and test of interlaminar shear strength indicated that the thermal polymerization of cyano groups improved the heat resistance of BMI resins and enhanced the interfacial adhesion at higher temperature.

Effect of organo-montmorillonite on mechanical properties of bismaleimide composites reinforced by glass fibre and carbon fibre

Organo-montmorillonite (OMMT) modified bismaleimide (BMI) nanocomposites were used as the matrix of glass fibre and carbon fibre reinforced composites. The effects of OMMT on the mechanical properties of BMI resin and fibre composites were investigated. Fourier transform infrared spectroscopy (FT-IR) analysis revealed that there exist interactions between OMMT and resin, which is useful for the delamination and dispersion of the silicate layers within the BMI matrix. Owing to the incorporation of OMMT, the impact strength, flexural strength and modulus of BMI resin were substantially improved. Moreover, the interlaminar shear strength (ILSS), flexural strength and modulus of fibre composites were enhanced. Scanning electron microscopy (SEM) photographs exhibited that the destruction modes of fibre composites were changed from interfacial destruction into the matrix destruction after the introduction of OMMT. In addition, it was found that the interfacial adhesion of glass fibre composite was improved more significantly than that of carbon fibre composite.

Preparation and Properties of Bismaleimide Resins of Aromatic Sulfone Ether Diamine

Aromatic sulfone ether diamine, bis[4-(4-aminophenoxy)phenyl]-sulfone (SED), was prepared by the nucleophilic aromatic substitution of 4,4'-dichlorodiphenylsulphone by p-aminophenolate. The reaction was conducted in the presence of excess potassium carbonate as a weak base, toluene as the dehydrating agent and N-methylpyrrolidone as the dipolar aprotic solvent. SED showed good solubility in common organic solvents, such as dioxan, tetrahydrofuran, butanone and acetone. SED was reacted with maleic anhydride to obtain aromatic sulfone ether bismaleimide, bis[4-(4-maleimidophenoxy)phenyl]-sulfone (SEM). The compounds were characterized by FTIR and 1 H NMR analysis. Furthermore, copolymer resins of SED with 4,4'-bismaleimidodiphenyl methane (BMI) and SEM were prepared. After curing, crosslinked resins with better thermal stability resulted. The temperature at maximum rate of weight loss (T max ) and the heat-resistant temperature index (T i ) in air were found to be 426°C, 208°C and 579°C, 221°C for BMI/SED and SEM/SED resins, respectively. Compared with the corresponding 4,4'-diaminodiphenyl methane (DDM) system, BMI/SED and SEM/SED showed a slight decrease in T max and T i . SED-modified BMI/amine resin based glass cloth laminates for printed circuit boards showed higher mechanical properties than those of the corresponding unmodified system. With SED instead of the original amine component in 3-5% weight fraction, the tensile strength, flexural strength and impact strength of the laminates increased markedly. Meanwhile, the stripping strength and weld resistance were also improved by the addition of SED.

Preparation and Properties of Bismaleimide Resins of Aromatic Sulfone Ether Diamine

Preparation and Properties of Bismaleimide Resins of Aromatic Sulfone Ether Diamine

Synthesis and properties of bismaleimide resins containing ether bonds

AbstractNew bismaleimides containing ether bonds were prepared. The thermal properties of the bismaleimides were investigated by differential scanning calorimetry (DSC). The effects of structure of the bismaleimides and curing conditions on the thermal and mechanical properties of the cured resins such as initial decomposition temperature (Td), glass transition temperature (Tg), and flexural strength were studied. The introduction of ether bonds to bismaleimide resins decreased the brittleness of the resins without reductions in their heat‐resistant properties.

Effect of triallyl cyanurate on the properties of bis‐maleimide resins

AbstractThis paper describes the improved processibility of 4,4'‐bis‐maleimidophenyl methane (BM) chain extended by 4,4'‐diaminodiphenyl methane (DADPM) by coreaction with triallyl cyanurate (TAC). Curing of BM, chain‐extended BM, and mixture of BM and DADPM (1 : 0.3 molar ratio) in the presence of 5, 10, 15, and 20% (w/w) of TAC was followed by differential scanning calorimetry (DSC) and thermal stability of cured resins was evaluated by thermogravimetric analysis. TAC had insignificant effect on char yield (at 800°C) of BM resin. Glass‐ and graphite fabric‐reinforced composites were fabricated using chain‐extended BM containing 10% TAC and methyl ethyl ketone (MEK) as solvent. Interlaminar shear strength was found to be 7620 psi for graphite fabric laminate containing 40% resin. Good retention of mechanical properties of laminates at 220°C up to 320 h was observed.