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With a shell of starch-melamine-formaldehyde (SMF) resin, core/shell-like ammonium polyphosphate (SMFAPP) is prepared by in situ polymerization, and is characterized by SEM, FTIR and XPS. The shell leads SMFAPP a high water resistance and flame retardance compared with APP in polypropylene (PP). The flame retardant action of SMFAPP and APP in PP are studied using LOI, UL 94 test and cone calorimeter, and their thermal stability is evaluated by TG. The flame retardancy and water resistance of the PP/SMFAPP composite at the same loading is better than that of the PP/APP composite. UL 94 ratings of PP/SMFAPP can reach V-0 at 30 wt% loading. The flame retardant mechanism of SMFAPP was studied by dynamic FTIR, TG and cone calorimeter, etc. [ABSTRACT FROM AUTHOR]

The two kinds of transition metal ion-incorporated nickel phosphates (TMIVSB-1) were synthesized by the hydrothermal method. The flame retardancy and thermal behavior of intumescent flame retardants (IFR), with and without TMIVSB-1 for PP, were investigated by LOI, UL-94 test, thermogravimetric analyses (TGA) and cone calorimetry. TMIVSB-1 can obviously improve the flame retardant behavior of IFR systems according to the results of LOI values and UL-94 test. The results of LOI show that 2 wt% TMIVSB-1 can increase the LOI value by 3-5 unit compared with that of PP/IFR composite. The UL-94 test shows that PP with 20% IFR burns and has no rating, but the addition of a small content 2 wt% of TMIVSB-1 with 18 wt% of IFR can reach a UL-94 V-0 rating. TGA results show that the thermal stability of PP/IFR/TMIVSB-1 increases obviously more than that of PP/IFR when the temperature is above 265°C. From cone calorimetry results, it can be observed that the HRR peaks are not obviously decreased, but the burning time of PP/IFR/FeVSB-1 (351s) and PP/IFR/ZnVSB-1 (380s) is obviously prolonged compared with that of PP/IFR (303s). The real time FTIR spectra (RTFTIR) demonstrates that the addition of TMIVSB-1 further staves the decomposition of the PP composites. The scanning electron microscopy (SEM) indicates the quality of char forming of PP/IFR/ TMIVSB-1 is superior to that of PP/IFR. [ABSTRACT FROM AUTHOR]

Cured epoxy resin (EP) composites containing Ammonium Polyphosphate (APP) and metallic oxide were prepared and characterized. The flame retardancy of the composites was studied using LOI, UL 94, cone calorimeter and Laser Raman spectroscopy, etc. The data of LOI, UL 94 and cone calorimeter show that APP is a good flame retardant for EP. The LOI value of the composite containing 20 wt% APP is as high as 38.0% and its UL 94 rating is raised to V-0. The addition of APP and La2O3 leads to the formation of char layer containing smaller carbonaceous microstructures compared with that of EP. Moreover, the thermo-oxidative decomposition of EP and its composites is characterized by dynamic FTIR. [ABSTRACT FROM AUTHOR]

Two novel dendritic poly(amido-amine) (PAMAM) bridged salicylaldimine ligands were synthesized by Schiff base reaction using 1.0 generation dendritic PAMAM as bridged groups. The cobalt complex with 1,4-butanediamine as core (C1) and the cobalt complex with 1,6-hexanediamine as core (C2) based on dendritic PAMAM bridged salicylaldimine ligands were prepared by metallic coordination reaction, respectively. The structures of the ligands and the dendritic cobalt complexes were characterized by fourier transform infrared (FTIR), ultraviolet spectra (UV), hydrogen nuclear magnetic resonance (1H NMR) and electrospray ionization mass spectra (ESI-MS). The complexes C1 and C2 were evaluated as catalyst precursors for ethylene oligomerization after being activated with methylaluminoxane (MAO), diethylaluminum chloride (Et2AlCl), ethylaluminium dichloride (EtAlCl2) and ethylaluminum sesquichloride (EASC). The dendritic cobalt complexes exhibited the highest activity and selectivity for high carbon oligomers with EASC as activator. Under the conditions of 1.0 MPa, 25°C and Al/Co molar ratio 1500, the catalytic activity and selectivity for C10–C20using C1 were 3.44×106g·(mol Co·h)−1and 76.53% after activation with EASC, and the catalytic activity and selectivity for C10–C20using C2 were 3.42×106g·(mol Co·h)−1and 84.50%, respectively. [ABSTRACT FROM PUBLISHER]

Microencapsulated ammonium polyphosphate with polyurethane resin (PUMAPP) was prepared by in situ polymerization and characterized by X-ray photoelectron spectroscopy (XPS). The flame retardation of PUMAPP/dipentaerythritol(DPER) and ammonium polyphosphate (APP)/DPER flame retarded polypropylene (PP)/ethylene propylene diene rubber (EPDM) composites were studied using limiting oxygen index (LOI), UL-94 test and cone calorimeter. Results demonstrated that the flame retardancy of the PP/EPDM/PUMAPP/DPER composites was better than that of the PP/EPDM/APP/DPER composites at the same additive loading. Real time Fourier transform infrared (FTIR) and thermogravimetric analysis (TG) were used to study the thermal degradation and stability of the PP/EPDM/PUMAPP/DPER composite. The hydrolytic stability of the flame retarded PP/EPDM composites was studied. It was found that the microencapsulation of APP with the PU resin leaded to a decrease in the particle's water solubility. Moreover, the synergistic effect of vinyltrimethoxysilane (VTMS) on the PP/EPDM/PUMAPP/DPER composite was also investigated. [ABSTRACT FROM AUTHOR]

A series of flame retarding biodegradable polylactic acid composites (FR-PLA) based on aluminum hypophosphite (AHP) and expanded graphite (EG) were prepared by the melt-compounding method. The effect of AHP and EG on the flame retardancy and thermal stability of PLA were investigated by thermogravimetric analysis (TGA), UL-94 vertical burning test, limiting oxygen index, microscale combustion calorimetry and cone calorimeter testing. The gas products of PLA and FR-PLA composites were investigated by TG-IR technology. TGA results showed that the FR-PLA composites presented higher char residue and reduced mass loss rate than neat PLA. Significant improvement of flame retardancy of PLA/AHP/EG composites indicated an excellent synergistic effect between AHP and EG. Cone calorimeter tests gave clear evidence that the combination of AHP and EG resulted in a significant reduction of the heat release rate (HRR) and total heat release (THR). TG-IR revealed that the combination of AHP and EG resulted in significant decrease of gas products. The char residue of FR-PLA composites were also investigated by scanning electron microscope, Fourier transform infrared spectra spectroscopy and X-ray photoelectron spectroscopy. Based on the analysis, possible flame retardant mechanism was discussed. [ABSTRACT FROM PUBLISHER]