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Phenolic novolac-type epoxy (EPN) resin composites were fabricated by reinforcing with cotton waste (CtW), along with aluminum hydroxide (AH), and boric acid (BA) particles under different filler loadings. For characterization, thermogravimetric analysis, scanning electron microscopy, differential scanning calorimetry, and water sorption tests were performed on the composites. The effects of the CtW, AH, and BA contents on the thermal, flame-retardant, and mechanical properties of the composites were investigated. The triple hybrid additive (CtW:BA:AH) with a ratio of 20:5:10 wt% exhibited the best mechanical and combustion properties. The tensile strengths of this composite and the neat EPN were determined as 95.7 ± 6.92 and 96.6 ± 4.77 MPa, respectively. The T50 temperatures of the BA- and AH-doped composites were higher than that of neat EPN. The highest char percentages were observed in the triple composites, while the lowest were observed in the EPN/CtW composites. The combustion of the triple composite with a CtW:BA:AH ratio of 20:5:10 wt% was spontaneously extinguished in 37 s. Horizontal flammability testing also showed better fire resistance for the CtW/BA/AH composites over their CtW counterparts, with the highest estimated limiting oxygen index of 32.3 obtained for the 20:5:10 wt% composite. The water sorption test results show that the CtW composites had the highest hydrophilicity, especially those with 30 wt% CtW or higher, in the presence of water at room temperature.

In the first stage of this study, the epoxy resin-hardener system, which was used in modification with thermoplastic polystyrene (PS) waste, was determined. For this purpose, different epoxy resins: bisphenol-A type (ER) and phenolic novolac (EPN) epoxy resins and modified cycloaliphatic amine type different curing agents were tried, and the EPN-IPOX system was found suitable. The curing degrees of the neat ER, EPN, and modified EPN (EPN-PS) resins calculated from the FTIR spectra were found as 99.3%, 99.9%, and 86.5%, respectively. The increase in the degree of curing increased the density values. Pristine (NC) and chemically modified (MNC) montmorillonite nanoclays were used in the preparation of nano- and hybrid composites. Chemical modification was accomplished by treating NC particles with tetramethylammonium chloride (TMAC). Chemical structures of nanoclays were elucidated by FTIR. The appropriate ratio of PS and NC was accepted as 4% and 2% by weight, respectively. Hybrid composites were produced at a fixed NC or MNC ratio of 2% by weight, with red mud waste (RMW) released during the production of alumina from bauxite. The surface morphology of nano- and hybrid composites was characterized by Scanning electron microscopy (SEM) and X-ray diffraction (XRD). A comparative study of the influence of 1–4 wt% pristine NC, and two-types binary systems; (a) 2 wt% NC-(15–35) wt% RMW; and (b) 2 wt% MNC-(15–35) wt% RMW on the mechanical, dynamic mechanical, and thermal properties of modified epoxy resin (EPN-PS) was investigated. Combustion of the EPN-PS matrix decreased with adding NC/MNC and RMW.

WOS: 000464781100001, In this study, the waste of sunflower oil refinement was converted to a fatty acid glycidyl ester (FAGE). An unsaturated oligo(ether-ester) (OEE) was synthesized by ring-opening polymerization using propylene oxide (PO) and FAGE. Oligo(ether-ester) production was achieved with a high yield of 80% at 5 h and 0 degrees C when the mole ratio of PO : FAGE was 1 : 1. Synthesized OEE was characterized by FTIR and several chemical analysis methods. According to the TGA results, T-5, T-10, and T-50 values of OEE-styrene copolymers increased up to a 7 : 3 mole ratio then decreased. The weight losses of these copolymers changed in the range of 3-5%. The data of longitudinal and transversal wave velocities showed that copolymers with styrene had better elastic properties and impact resistances compared to those with pure polystyrene., Selcuk University Scientific Research FoundationSelcuk University, The authors acknowledge the Selcuk University Scientific Research Foundation for the financial support.

International audience; The epoxy resin used in this study is modified with 5 wt% of polyaniline. Then electrically conductive modified epoxy resin (MER) (as matrix) and different weight amounts (10–30 wt%) of andesite waste (AW) as filler are mixed together to obtain the andesite waste-reinforced epoxy resin composites. The effects of filler amount on the electrical and ultrasonic properties of the modified epoxy resin are examined. The effects of AW amount on the ultrasonic properties of the obtained MER/AW composites are investigated by ultrasonic pulse-echo method. The conductivity of the composites is measured by a four-point probe (FPP) method, and the morphologies of the samples are investigated by scanning electron microscopy (SEM). Experimental results show that increasing the amount of AW causes a linear increase in the elastic properties. On the other hand, the same amounts of AW decrease the electrical conductivity of MER.

In this study, precipitated calcium carbonate-lime waste (LW) from sugar beet production was recycled as a raw material for the preparation of composite materials. Epoxidized soybean oil (ESO) was used as a co-matrix in 50 wt% with bisphenol A-type epoxy resin (ER). The composites were prepared with LW in varied per cent values (10 − 50 wt%) using the casting technique. The morphology of the composites was characterized by X-ray diffraction and scanning electron microscopy. Effects of ESO and LW amounts on the mechanical and thermal properties of the composites were investigated. Modification with ESO remarkably enhanced the plasticity of the material, but decreased the curing degree about 2%. The modified ER shows about 13% increase in elongation at break over the pure epoxy matrix. Density and hardness of neat epoxy matrices were observed to increase with the LW content in the composite. Tensile strengths of all composites are higher than that obtained with neat epoxy. The thermogravimetric analyses show that ESO and LW significantly improve the thermal stability of neat ER at the temperatures above 300°C. The best thermal results were obtained with the composites containing 40- and 50 wt% LW. The residual weights of the composites are higher than that of neat ER and ER-ESO, and increases with the increasing LW amount. The T5, T10 and T50 data of the composites are higher than those of neat ER and ER-ESO. The water sorption values of the ER-ESO matrix composites are in the range of 1.0 − 2.9 wt%. POLYM. COMPOS., 2016. © 2016 Society of Plastics Engineers

The purpose of this study is to develop epoxy composites with improved mechanical, thermal, and electrical properties. Semiconducting glass (SG) binary systems such as As2S3-TlS and As2Se3-TlS were synthesized in various mole ratios (1:1 and 1:3). Electrically conductive DGEBA-type epoxy-SG-filled composites were developed containing 1–15 wt% of fillers and characterized by X-ray diffraction and scanning electron microscopy techniques. As a result, the effects of the type and amount of semiconductive filler on the mechanical, thermal, and electrical properties of commercial epoxy resins (ERs) were examined. It was found that I2 doping of the filler significantly increased the electrical conductivity of the composites up to 10−3 S cm−1. Percolation concentrations were found to be 7 wt% for all composites studied. The maximum tensile strength changed in the range of 86–114 MPa was obtained with 5–10 wt% of SG particles. In addition, the thermal behavior and stability of the epoxy composites were studied using thermogravimetric analysis. The incorporation of SG particles increased the 10% decomposition temperature of neat epoxy by 5–35°C. ER/SG coatings showed the best adhesion results and perfect resistance to 3% NaCl, 3% HCl, and 5% NaOH solutions. POLYM. COMPOS., 2016. © 2016 Society of Plastics Engineers

During the past two decades, photoinitiated polymerization has been attracting a great interest in terms of scientific and industrial activity. The wide recognition of UV treatment in the polymer industry results not only from its many practical applications but also from its advantage for low-cost processes. Unlike most thermal curing systems, radiation-curable systems can polymerize at room temperature without additional heat, and the curing is completed in a very short time. The advantage of cationic UV technology is that post-cure can continue in the ‘dark’ after radiation. In this study, bio-based acrylated epoxidized soybean oil (AESO) was cured with UV radiation using radicalic photoinitiator Irgacure 184. Triarylsulphonium hexafluoroantimonate was used as cationic photoinitiator for curing of 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate. The effect of curing time and the amount of initiators on the curing degree and thermal properties were investigated. The thermal properties of the coating were analyzed after crosslinking UV irradiation. The level of crosslinking in the coating was evaluated by FTIR analysis. Cationic UV-cured coatings demonstrated excellent adhesion and corrosion resistance properties. Therefore, our study holds a great potential with its simple and low-cost applications., {"references":["C. Decker, Progr. Polym. Sci., 21, 593 (1993).","D. K. Chattopadhyay, S.S. Panda, K.V.S.N. Raju, Prog. Org. Coat., 54, 10 (2005).","D. H. Klein, Kjorg, T. Dinnissen, Surf. Coat. Int., 12, 558 (1998).","A. Noomen, JOCCA, 64, 347 (1981).","A. Udagawa, F. Sakurai, T. Takahashi, J. Appl. Polym. Sci., 42, 1861 (1991).","I. Ozaytekin, H. Turedi, G. Ahmetli, Polym. Compos. (2015), doi: 10.1002/pc.23542 (2015).","S.J. Park, F.-L. Jin, J.-R. Lee, Mater. Sci. Eng. A, 374, 109 (2004)."]}

In this study, precipitated calcium carbonate lime waste (LW) from sugar beet process was recycled as the raw material for the preparation of composite materials. Epoxidized soybean oil (ESO) was used as a co-matrix in 50 wt% with DGEBA type epoxy resin (ER). XRD was used for characterization of composites. Effects of ESO and LW filler amounts on mechanical properties of neat ER were investigated. Modification of ER with ESO remarkably enhanced plasticity of ER., {"references":["Sh. Masharipova, Application of Defecation Lime from Sugar Industry in Uzbekistan, Master of Sience Thesis, Stockholm (2006).","G. Vaccari, E. Tamburini, G. Sgualdino, K. Urbaniec, and J. Klemes, J. Cleaner Product., 13, 499 (2005).","E. Sarka, Z. Bubnik, P. Kadlec, and A. Vesela-Trilcova, J. Food Eng., 87, 45 (2008).","P. Allen and N. Padayachee, Proc. S. Afr. Sug. Technol. Ass., 84, 510 (2011).","H.H. Cai, S.D. Li, G.R. Tian, H.B. Wang, and J.H. Wang, J. Appl. Polym. Sci., 87, 982 (2003).","L. Zhang, C. Li, and R. Huang, J. Polym. Sci. Part B, 42, 1656 (2004).","P. Supaphol, W. Hrnsiri, and J. Junkasem, J. Appl. Polym. Sci., 92, 201 (2004).","G. Ahmetli, M. Dag, H. Deveci, and R. Kurbanli, J. Appl. Polym. Sci., 125, 24 (2012).","G. Ahmetli, N. Kocak, M. Dag, and R. Kurbanli, Polym. Compos, 33, 1455 (2012).\n[10]\tL.E. Neilsen, R.F. Landel, Mechanical properties of polymers and composites, Marcel Dekker, Inc., New York (1994). \n[11]\tPham, H.A., Marks, M.J., Epoxy resins, v.9, in: Encyclopedia of Polymer Science and Technology, John Wiley & Sons, New York (2003).\n[12]\tF.P. Beer, E.R. Johnston, and J.T. De Wolf, Mechanics of Materials (5th McGraw Hill, New York (2009).\n[13]\tF.W. Billmeyer, Textbook of Polymer Science, John Wiley & Sons, New York (1984)."]}

WOS: 000385159000001, Epoxy resin (ER) was modified with four different epoxide compounds, 4,5-epoxy-4-methyl-pentane-2-on (EMP), 3-phenyl-1,2-epoxypropane (PhEP), 1-chloro-2,3-epoxy-5-(chloromethyl)-5-hexene (CEH), and a fatty acid glycidyl ester (FAGE), to improve its chemical and physical properties. The effects of the addition and amount of these modifiers on mechanical, thermal, and coating properties were investigated. Atomic force microscopy was used to observe the changes obtained with the modification. The influence of the modifying agents on the curing process was monitored through FTIR spectroscopy. The curing degrees of ER and modified ERs (M-ERs) were found to be over 91%. The results showed that tensile strength of ER improved till 30% (wt.) with addition of the modifier content. Modification with EMP and PhEP remarkably enhanced the thermal stability of ER to be highly resistant to the corrosive media.

In this research, epoxy toluene oligomer (ETO) was synthesised from toluene and epichlorhydrin, which was used as co-matrix in 50 wt.% with commercial epoxy resin (ER). Its chemical structure was characterised with FTIR spectroscopy and chemical analyses. ETO was found as an effective flame retardant for ER. Modification of ER with ETO in 50 wt.% increased percentage elongation at break of neat ER about 67 times. The rigid filler used in epoxy polymer matrix was the modified and unmodified sepiolite. The appropriate sepiolite amount in all cases was determined to be 5 wt.%. Scanning electron microscopy (SEM) was used for characterisation of surface and cross sections of the composites to verify the results. Modification of sepiolite increases the T 5 , T 10 , and T 50 of neat ETO–ER by 10, 7, and 5 °C, respectively. Surface hardness and tensile strength of all composites were higher than those of neat ETO–ER polymer matrix. ETO–ER/modified sepiolite coating showed the best adhesion results and exhibited perfect resistance to 3% NaCl and 10% NaOH solutions.

Fatty acid waste was recycled as raw material and utilized to synthesize epoxy (HP) or unsaturated ester group (OEE) containing polymers. The radicalic polymerization between the styrene and itaconic acid was carried out, too. Glycidyl ester of styrene-itaconic acid copolymer was obtained by esterification reaction with epichlorohydrin. The polymers were characterized by means of Fourier transform infrared spectroscopy and chemical analysis. The polymers were incorporated into diglycidyl ether of bisphenol A type commercial epoxy resin to prepare composites. The effects of polymer structure and amount on the physico-mechanical and thermal properties of epoxy were investigated. Surface hardness, tensile strength, percentage elongation and stress at maximum load of the composites were obtained higher than pure epoxy resin. The composites reinforced with bio-based polymers showed about 74.55–243% increase in elastic modulus over the pure epoxy matrix. Obtained Young's modulus values were higher for composites with styrene-based polymers. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Unsaturated oligo(ether–ester) was prepared by ring-opening polymerization of butylene oxide (BO) with glycidyl methacrylate (GMA) in the presence of cationic catalyst BF3•O(C2H5)2. The effects of mol ratio of the initial components, amount of catalyst, temperature, and reaction times on the copolymerization reaction were examined. Oligo(ether–ester) were achieved in highest yield of 82% after reaction times of 4 h at 0°C. Synthesized copolymer was characterized using spectroscopic (1H NMR and IR) and chemical analysis methods. The thermal degradation and softing points of oligo(ether–ester)-styrene composites were studied. It is shown that crosslinking of the unsaturated oligo(ether–ester) with styrene takes place through the use of thermostable materials. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008.

The purpose of this study is to develop the semiconductive composites. Semiconducting glass (SG) binary system Sb2S3–Yb3S4 in mole ratio 1:1 was synthesized and was doped with I2. Next, electrically conductive DGEBA-type epoxy resin (ER)/SG-filled composites and epoxy toluene oligomer (ETO) modified epoxy resin-SG filled composites were developed with 3–10 wt. % of fillers and characterized. As a result, the effects of the modifier and amount of semiconductive filler on the electrical properties of commercial epoxy resin were examined. Percolation concentration was 7 wt. % for all composites. For the SG-reinforced composites, the dispersion of the fillers is investigated by X-ray diffraction (XRD) and by scanning electron microscopy (SEM).

The purpose of this study is to investigate the effects of the type and amount of semiconductive fillers on the elastic properties of epoxy (ER) / semiconductive glass (SG) composites by ultrasonic velocity measurments. Different semiconducting glasses (SG) binary systems such as As2S3-TlS and As2Se3-TlS were synthesized. ER/SG composites were formed 15 wt. % of fillers and characterized by ultrasonic velocity measurments. The ultrasonic wave velocities of composites were measured with the pulse-echo method at room temperature by a flaw detector. The values of the acoustic impedance, Poisson's ratio, and elasticity constants of the samples were calculated by the measured values of both longitudinal and shear ultrasonic wave velocities. According to the results, The highest elastic properties values were found in the ER/SG-3 composite using 50% As2Se3-50% TlS.

BALTIC POLYMER SYMPOSIUM 2014 -- SEP 24-26, 2014 -- Laulasmaa, ESTONIA, WOS: 000366504000002, Epoxy toluene oligomers (ETO) are very important substances due to effective functional groups in their structure and they are especially used as polymer additives that have been synthesized from toluene and epichlorhydrin. Flame-retardant properties of the neat epoxy resin (ER), ETO, and ETO/ER blend thermoset were evaluated by UL94 vertical flammability test. The chlorine atoms in ETO increase the stability of the polymer material against burning. For the synthesis other polymers, first the waste product of the industrial vegetable oil refinement acid oil was transformed into the glycidyl ester (FAGE). Unsaturated oligo(ether-ester) (OEE) was prepared by ring-opening polymerization of the propylene oxide (PO) with FAGE in the presence of cationic catalyst BF3 center dot O(C2H5)(2). Its chemical structure was characterized with FTIR spectroscopy. These polymers, isoamyl methacrylate (AMA) and 1,2-epoxy-hexane-5-en (EH) were used as modifiers in the DGEBA-type epoxy resin. The effects of the modifier structure and amount on the mechanical properties of epoxy were investigated. Tensile strength and Young's modulus of the modified samples were found higher than those of the neat epoxy resin., Tallinn Univ Technol