Flame retardancy effects of zinc borate and nanoclay in ABS, and boron compounds in PET

Özkaraca, Ayşe Çağıl
In this thesis there were two main purposes, the first one being to investigate effects of zinc borate (ZB) on the flammability behavior of ABS when used with and without a traditional brominated flame retardant (BFR) / antimony trioxide (AO) system. The second purpose was to investigate contribution of nanoclays (NC) to the flame retardancy performance of the same traditional BFR compound with various combinations of AO and ZB again in ABS matrix. For these purposes, materials were melt compounded by using a laboratory scale twin-screw extruder, while specimens were produced by injection or compression molding. Flame retardancy of the specimens were investigated by Mass Loss Cone Calorimeter (MLC), Limiting Oxygen Index (LOI) measurements and UL-94 vertical burning tests. Other characterization techniques required in this thesis were; X-ray diffraction analysis, scanning and transmission electron microscopy, thermogravimetric analysis and tensile tests. Studies for the first purpose indicated that almost all flame retardancy parameters were preserved when antimony trioxide were replaced with zinc borate as much as in the ratio of 1:3. Residue analyses revealed that predominant flame retardancy mechanism of traditional system was gas phase action, while zinc borate contributes especially in the condensed phase action by forming thicker and stronger char layer. Investigations for the second purpose basically concluded that use of nanoclays improved all flame retardancy parameters significantly. Residue analyses pointed out that nanoclays especially contribute to the formation of stronger and carbonaceoussilicate char acting as a barrier to heat and flammable gases and retarding volatilization via tortuous pathway. As an additional third purpose in this thesis, usability of three boron compounds (zinc borate ZB, boric acid BA, boron oxide BO) with two traditional flame retardants (organic phosphinate OP and melamine cyanurate MC) in neat PET and recycled PET were also examined leading to some promising results in MLC parameters.


Thermal characterization of composites of polyamide-6 and polypropylene involving boron compounds via direct pyrolysis mass spectrometry
İşbaşar Afacan, Güllü Ceyda; Hacaloğlu, Jale; Yılmazer, Ülkü; Department of Polymer Science and Technology (2013)
In this work, the effects of addition of boron compounds, boron phosphate (BPO4), zinc borate (ZnB), borosilicate (BSi) and lanthanum borate (LaB), on thermal degradation characteristics of composites of polyamide 6 (PA6) and polypropylene (PP) are analyzed via Direct Pyrolysis Mass Spectrometry (DP-MS) technique. The composites of PA6 involve nitrogen containing flame retardants, melamine (Me) or melamine cyanurate (MC); or phosphorus containing flame retardant, aluminum diethylphosphinate (AlPi), with or ...
Synergistic effect of boron containing substances on flame retardancy and thermal stability of intumescent polypropylene composites
Yılmaz, Ayşen; BAYRAMLI, ERDAL (2010-12-01)
The synergistic effect of four different boron containing substances, zinc borate (ZnB), borophosphate (BPO4), boron silicon containing preceramic oligomer (BSi) and lanthanum borate (LaB), were studied to improve the flame retardancy of a polypropylene (PP) intumescent system composed of ammonium polyphosphate (APP) and pentaerythritol (PER). The flame retardancy of PP composites was investigated by limiting oxygen index (LOI). UL-94 standard, thermogravimetric analysis (TGA) and cone calorimeter tests. Th...
The flame retardant effect of aluminum phosphinate in combination with zinc borate, borophosphate, and nanoclay in polyamide-6
DOĞAN, Mehmet; Bayramlı, Erdal (2014-01-01)
The effect of zinc borate (ZnB), borophosphate (BPO4), and organoclay were studied to improve the flame retardancy of polyamide-6 composites containing organic phosphinates. The flame retardancy of polyamide-6 composites was investigated using limiting oxygen index (LOI), Underwriters Laboratories (UL-94) standard, thermogravimetric analysis, Fourier transform infrared spectroscopy, and mass loss calorimeter. The addition of 15wt% aluminum phosphinate (AlPi) increased the LOI value from 22.5 to 29.5, and V0...
The effect of boron substitution on cyclacenes
Türker, Burhan Lemi; Azizoglu, A (2001-01-15)
AM1-type semiempirical molecular orbital treatment was performed on the Huckel-type cyclacenes having certain number of boron atoms at the peri-positions and at the fusion sites of the arenoid rings. The effect of boron atoms is generally destabilizing in all the cases as compared to their unsubstituted cyclacene counterparts. The AM1 results revealed that certain properties of the boron-substituted cyclacenes are affected not only by the number of arenoid rings they have but also by the nature of their per...
Production of boron nitride by carbothermic and mechanochemical methods, and nanotube formation
Camurlu, HE; Aydogdu, A; Topkaya, Yavuz Ali; Sevinc, N (2003-09-12)
The formation of hexagonal boron nitride by carbothermic reduction of boron oxide and nitridation has been examined. Experiments were conducted in the temperature range of 1100-1500degreesC for durations between 15-240 minutes. Products were examined by X-ray, SEM and chemical analysis. The results showed that the reaction proceeds through a gaseous boron containing species, which is most probably 13203(g). It was found that all of the carbon was consumed and formation of boron nitride was complete in 2 hou...
Citation Formats
A. Ç. Özkaraca, “Flame retardancy effects of zinc borate and nanoclay in ABS, and boron compounds in PET,” M.S. - Master of Science, Middle East Technical University, 2011.