Amine-terminated Butadiene Acrylonitrile Research Articles

Effect of amine‐reactive elastomer on the properties of poly(lactic acid) films obtained by solvent‐cast 3D printing

AbstractBlends of poly(lactic acid) (PLA) and amine‐terminated butadiene‐acrylonitrile (ATBN) elastomer were prepared by solution with ATBN contents of 8–20 wt%. Films were molded by liquid deposition modeling 3D printing. Fourier transform infrared (FTIR) spectroscopy showed that the terminal carboxylic groups of the PLA chains reacted with the terminal amino groups of ATBN. Water was the byproduct of this reaction, causing PLA hydrolysis and accelerating the reaction. Thermogravimetric analysis (TGA) showed that components interaction caused a loss of PLA thermal stability. Scanning electron microscopy (SEM) of the blends revealed a porous morphology and no phase separation. There was change in the elongation when compared with neat PLA. Although the addition of a telechelic elastomer could improve PLA toughness, any benefits arising from such addition seem to be neutralized by PLA chain scission due to hydrolysis and porosity, resulting from the condensation reaction.

Influence of titanium oxide fillers on the tensile and flexural properties of E-glass fabric/epoxy composites

In present scenario E-Glass fabric polymer is playing a major role in the field of structural and aerospace. The elemental composition of filler materials and its size of particles play a vital role in the development of mechanical and physical characteristics of micro filler integrated polymer matrix composites. In this paper E- glass fabric/epoxy composite materials are modified by adding the combination of Titanium oxide (TiO2) and amine terminated butadiene acrylonitrile (ATBN) to improve the mechanical properties. Vacuum bagging method is employed to develop the polymer matrix composites and the composites are experienced underneath tensile and flexural test at room temperature in order to scrutinize the strength. Scanning electron microscopy analysis used to identify the mode of failure of the composite, debonding and pull out of fiber is observed in the composites. Agglomeration of micro filler materials in the matrix is observed in scanning electron microscopy images which reveal micro structural information of fractured surfaces of composites. The mechanical characterization results showed that the tensile and flexural strength of developed composites are comparable to the strength of the E-glass fabric.

Enhancing the heat and load transfer efficiency by optimizing the interface of hexagonal boron nitride/elastomer nanocomposites for thermal management applications

Amine-terminated butadiene-acrylonitrile (ATBN) was covalently grafted on a hexagonal boron nitride (BN) surface to enhance the interface affinity between BN and a carboxylated styrene-butadiene rubber (XSBR) matrix for preparing thermal interface materials with robust thermo-physical properties. The strong attraction between the amino groups on the ATBN-functionalized BN (ABN) and the carboxyl groups on the XSBR chains can further enhance the interfacial adhesion between the fillers and polymer matrix. The mechanical properties, thermal stability, thermal conductivity, thermo-physical properties, and interfacial filler–matrix network of the prepared XSBR/ABN nanocomposites were studied. The XSBR/ABN nanocomposites exhibited better mechanical and thermo-physical behavior compared to the XSBR/BN nanocomposites over the entire range of filler concentration, representing an enhanced interfacial interaction owing to functionalization. Moreover, the XSBR/ABN nanocomposites exhibited superior thermal conductivity as compared to the XSBR/BN nanocomposites, with the former exhibiting approximately 490% higher thermal conductivity than neat XSBR, whereas the latter exhibited 395% higher thermal conductivity than neat XSBR at a filler loading of 90 phr.

Investigation on Rubber-Modified Polybenzoxazine Composites for Lubricating Material Applications

Effects of liquid amine-terminated butadiene-acrylonitrile (ATBN) on the properties of bisphenol-A/aniline-based polybenzoxazine (PBA-a) composites were investigated. Liquid ATBN decreased gel time and lowered curing temperature of the benzoxazine resin (BA-a). The PBA-a/ATBN-based self-lubricating composites resulted in substantial enhancement regarding their tribological, mechanical, and thermal properties. The inclusion of the ATBN at 5% by weight was found decreasing the friction coefficient and improved wear resistance of the PBA-a/ATBN composites. Flexural modulus and glass transition temperature of the PBA-a composite samples added the ATBN was constant within the range of 1-5% by weight. A plausible wear mechanism of the composites is proposed based on their worn surface morphologies. Based on the findings in this work, it seems that the obtained PBA-a/ATBN self-lubricating composites would have high potential to be used for bearing materials where low friction coefficient, high wear resistance, and modulus with good thermal property are required.

Effect of Rubber Contents on Tribological and Thermomechanical Properties of Polybenzoxazine

Bisphenol-A/aniline based polybenzoxazine (PBZ) modified with amine terminated butadiene–acrylonitrile (ATBN) were prepared. The tribological and thermomechanical properties as well as thermal stability of the PBZ/ATBN copolymers were investigated by ball-on-disc tribometer, dynamic mechanical analysis (DMA), universal test machine and thermogravimetric analysis (TGA). The inclusion of ATBN at a mass fraction of 5% was found to greatly increase friction coefficient and wear resistance of the copolymers. DMA measurements showed that the storage modulus and the glass transition temperature of the PBZ can be maintained with an addition of ATBN in the range of 1-5wt%. Moreover, flexural property measurements indicated that the flexural strength of the copolymer increased with increasing of ATBN content up to 10wt% whereas TGA results revealed that an increase of the PBZ content can help improve thermal stability of the copolymers.

Effects of amino‐functionalized carbon nanotubes on the properties of amine‐terminated butadiene–acrylonitrile rubber‐toughened epoxy resins

ABSTRACTAmino‐functionalized multiwalled carbon nanotubes (MWCNT‐NH2s) as nanofillers were incorporated into diglycidyl ether of bisphenol A (DGEBA) toughened with amine‐terminated butadiene–acrylonitrile (ATBN). The curing kinetics, glass‐transition temperature (Tg), thermal stability, mechanical properties, and morphology of DGEBA/ATBN/MWCNT‐NH2 nanocomposites were investigated by differential scanning calorimetry (DSC), thermogravimetric analysis, a universal test machine, and scanning electron microscopy. DSC dynamic kinetic studies showed that the addition of MWCNT‐NH2s accelerated the curing reaction of the ATBN‐toughened epoxy resin. DSC results revealed that the Tg of the rubber‐toughened epoxy nanocomposites decreased nearly 10°C with 2 wt % MWCNT‐NH2s. The thermogravimetric results show that the addition of MWCNT‐NH2s enhanced the thermal stability of the ATBN‐toughened epoxy resin. The tensile strength, flexural strength, and flexural modulus of the DGEBA/ATBN/MWCNT‐NH2 nanocomposites increased increasing MWCNT‐NH2 contents, whereas the addition of the MWCNT‐NH2s slightly decreased the elongation at break of the rubber‐toughened epoxy. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40472.

Property enhancement of epoxy resin using a combination of amine-terminated butadiene–acrylonitrile copolymer and nanoclay

The present work investigates the effect of organomodified nanoclay (ZW1) and butadiene–acrylonitrile copolymer terminated with amine group (ATBN copolymer) on the properties of epoxy resin (EP). The impact strength (IS) and the critical stress intensity factor ( KC) values of EP containing 1% nanoclay increased approximately by 200% and 75%, respectively, in relation to neat EP. Moreover, hybrid composites containing 1% or 2% nanoclay and ATBN showed improved mechanical properties in relation with unmodified EP. The magnification and analysis of the Fourier-transform infrared spectra showed an increase in the peak height of 3338 cm-1 due to polymeric modifier incorporation. This finding might be explained by the reaction between modifier or hardener amine groups and the unreacted part of EP cured at room temperature. Hybrid composite containing 2% Nanobent ZW1 and 5% ATBN exhibited synergistic effect in terms of tensile adhesive strength toward composites with one modifier. Moreover, scanning electron micrographs showed more elongated and leaf-like structure for hybrid compositions, explaining the enhancement of IS and KC values of the tested composites.

Effect of annealing on phase separation and mechanical properties of epoxy/ATBN adhesive

Amine-terminated butadiene acrylonitrile (ATBN) was applied as curing agents for diglycidyl ether of bisphenol A epoxy resin without any accelerating agent. ATBN weight percentage of 59–82wt% was used, so that the soft ATBN domains in the cured samples formed a continuous phase, while the hard epoxy domains formed a discontinuous phase. Mechanical properties were tested in the means of strain-stress and adhesive strength. The results showed that the samples had excellent toughness at temperatures above the flexible segment glass transition temperature (Tg1), and it was well maintained after annealing at 150°C. However, adhesive strength of the annealed sample decreased dramatically when the testing temperature was close to the rigid segment glass transition temperature (Tg2). It was observed that (Tg2) decreased and phase separation became weaker after the annealing. Real-time Fourier transform infrared (FTIR) measurement indicated that this phenomenon was related to the disassociation of hydrogen bonding within the hard domain caused by the increased mixing of the hard segments into the soft domains by the high temperature annealing. It was confirmed by transmission electronic microscope (TEM) test.

Effect of amine‐terminated butadiene‐acrylonitrile/clay combinations on the structure and properties of epoxy nanocomposites

AbstractThe effect of the clay content and the method of its combination with amine‐terminated butadiene‐acrylonitrile (ATBN) on the structure and behavior of epoxy was studied. In the case of the simultaneous addition of both components, the increasing clay content had a very small effect on the size of the reaction‐induced phase separation‐formed particles at 5% rubber content due to predominant elimination of two major clay effects, i.e., the nucleation due to phase separation and the kinetics. As a result, both the time window between the onset of phase separation and vitrification and the viscosity at the cloud point did not change significantly. The minor change in the particle size/clay content dependences with different curing temperatures indicates that the balance between the two clay effects shifted. The corresponding study of the mechanical behavior indicated that the best balanced mechanical properties were obtained at certain clay/ATBN ratios, and thus, there was synergy between the components. Similar mechanical parameters were obtained for the application of both components in the form of ATBN/montmorillonite intercalate. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Fracture toughness of a hybrid‐rubber‐modified epoxy. I. Synergistic toughening

AbstractThe fracture behavior of a hybrid‐rubber‐modified epoxy system was investigated. The modified epoxy included amine‐terminated butadiene acrylonitrile (ATBN) rubber and recycled tire particles as fine and coarse modifiers, respectively. The results of the fracture toughness (KIC) measurement of the blends revealed synergistic toughening in the hybrid system when 7.5‐phr small particles (ATBN) and 2.5‐phr large particles (recycled tire) were incorporated. Transmission optical micrographs showed different toughening mechanisms for the blends; fine ATBN particles increased the toughness by increasing the size of the damage zone and respective plastic deformation in the vicinity of the crack tip. However, in the case of hybrid resin, coarse recycled rubber particles acted as large stress concentrators and resulted in the branching of the original crack tip. Mode mixity at the branch tips led to synergistic KIC in the hybrid system. It seemed that the ductility of the matrix played an effective role in the nature of the crack‐tip damage zone in the hybrid epoxies. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Fracture toughness of a hybrid rubber modified epoxy. II. Effect of loading rate

AbstractEffect of loading rate on toughness characteristics of hybrid rubber‐modified epoxy was investigated. Epoxy was modified by amine‐terminated butadiene acrylonitrile (ATBN) and recycled tire. Samples were tested at various loading rates of 1–1000 mm/min. Fracture toughness measurements revealed synergistic toughening in hybrid system at low loading rates (1–10 mm/min); hybrid system exhibited higher fracture toughness value in comparison with the ATBN‐modified resin with same modifier content. However, synergistic toughening was eliminated by increasing the loading rate. At higher loading rates (10–1000), the fracture toughness of hybrid system decreased gradually to the level lower than that of ATBN‐modified epoxy. Fractography of the damage zones showed the toughening mechanisms of ATBN‐modified system was less affected by increasing the loading rate compared to that of hybrid system. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Evaluation of clay hybrid nanocomposites of different chain length as reinforcing agent for natural and synthetic rubbers

Polymer nanocomposites are one of the highly discussed research topics in recent time. It has been reported in the present paper the preparation and the properties of different nanoclays based on sodium montmorillonite (bentonite) and some organic amines of varying chain lengths (dodecylamine, hexadecylamine and octadecylamine) beside amine-terminated butadiene–acrylonitrile copolymer (ATBN). The hybrid clays have been characterized with the help of Fourier Transform Infrared spectroscopy (FTIR). Transmission electron microscopy (TEM), Scanning electron microscopy (SEM), Wide angle X-ray diffractions (WXRD), and Thermogravimetric analysis (TGA). X-ray results showed that the intergallery distance of the clay is increased as a result of the intercalation of the amines and ATBN. The nanocomposite clays were incorporated in natural and synthetic rubbers (NR, SBR and NBR). The physico-mechanical properties are greatly improved with loading low concentrations of the nanocomposite clays compared with carbon black.

Exploring the tensile strain energy absorption of hybrid modified epoxies containing soft particles

In this paper, tensile strain energy absorption of two different hybrid modified epoxies has been systematically investigated. In one system, epoxy has been modified by amine-terminated butadiene acrylonitrile (ATBN) and hollow glass spheres as fine and coarse modifiers, respectively. The other hybrid epoxy has been modified by the combination of ATBN and recycled Tire particles. The results of fracture toughness measurement of blends revealed synergistic toughening for both hybrid systems in some formulations. However, no evidence of synergism is observed in tensile test of hybrid samples. Scanning electron microscope (SEM), transmission optical microscope (TOM) and finite element (FEM) simulation were utilized to study deformation mechanisms of hybrid systems in tensile test. It is found that coarse particles induce stress concentration in hybrid samples. This produces non-uniform strain localized regions which lead to fracture of hybrid samples at lower tensile loading and energy absorption levels.

Loading Rate-Induced Transition in Toughening Mechanism of Rubber-Modified Epoxy

The effect of loading rate on toughening mechanisms of rubber-modified epoxy resin was investigated using amine-terminated butadiene acrylonitrile (ATBN) rubber. Rubber-modified samples were tested at various loading rates in the range of 1–1000 mm/min. At low loading rates, modified resin exhibited a high fracture toughness, which decreased by increasing the rate of loading. At higher loading rate a transition region was observed, where the fracture toughness did not change noticeably with increasing the loading rate. Beyond the transition region, the resin fracture toughness dropped dramatically to the level of unmodified epoxy. Fractography of the damage zone showed different toughening mechanisms for the various loading rate regions, i.e., shear yielding and crack branching. It is believed that the interaction between these two toughening mechanisms, each dominating in one extreme loading rate condition, is responsible for the intermediate transition region, where toughness is virtually independent from loading rate.

Investigation of the fracture resistance in hoop wound composites modified with two different reactive oligomers

Rubber modification of hoop filament wound epoxy composites was investigated using amine-terminated butadiene acrylonitrile (ATBN) and carboxyl-terminated butadiene acrylonitrile (CTBN) oligomers. Both mechanical and physical properties of modified composites were investigated and the morphology of the samples was studied via scanning electron microscopy. Results indicated that, when added to the epoxy matrix, ATBN effected a superior increase in toughness, yet a more severe decline in compressive and flexural strength, compared to CTBN. In contrast, in the case of composite samples, incorporation of ATBN led to more favorable mechanical properties, from the viewpoint of both toughness and strength, relative to CTBN. This curious observation was generally attributed to the different amounts of rubber–epoxy precipitation and fiber–matrix adhesion, as well as various degrees of cavitation.

Use of rubber modification technique to improve fracture-resistance of hoop wound composites

Toughness improvement of an epoxy resin and respective hoop wound composite were investigated systematically using amine-terminated butadiene acrylonitrile (ATBN) liquid rubber. Rubber modification improves fracture toughness of epoxy resin with slight reduction in the glass transition temperature ( T g), flexural and compressive properties of resin. Impact resistance of composite is improved by rubber modification similar to modified resin. Interlaminar shear strength (ILSS), compressive modulus and strength, and flexural strength of composite decreased slightly with rubber modification. To interpret the data, the void content of composite samples was determined and the damaged surfaces of fractured samples were investigated. The findings explained the performance of rubber modified specimens in comparison with the unmodified one. In addition, a simple formulation was developed to predict the impact strength of modified composite samples.

Ground rubber/acrylonitrile–butadiene–styrene composites

A range of ground rubber (GR)/acrylonitrile–butadiene–styrene (ABS) composites were developed that contained untreated and various treated rubber particles. The tensile properties of the composite materials were significantly improved over the untreated GR/ABS sample either by a two-step treatment process involving surface chlorination of the GR followed by grafting of either amine-terminated butadiene acrylonitrile (ATBN) or triethanolamine zirconium chelate (TEAZ) molecules, or via in situ compatibilization of the chlorinated GR (Cl-GR) and the ABS matrix with the addition of up to 2% of Lewis acid catalysts such as AlCl 3, FeCl 3, or ZnCl 2. In comparison with the properties of the untreated GR/ABS composite, the two-step treatment provided an increase of up to 18% in tensile strength, 17% in Young’s modulus, and 83% in tensile toughness, whilst the in situ compatibilization approach led to increases in these properties of up to 46%, 33%, and 217%, respectively when 2 wt% AlCl 3 was added during the compounding stage of the composites. The tensile properties of the different GR/ABS composites were determined in accordance to the Australian Standard 1145–1989, whilst the surface chemistry of the untreated and surface-treated GR was characterized by X-ray photoelectron spectroscopy (XPS).

Modification of epoxy resin using reactive liquid (ATBN) rubber

Epoxy resins are widely utilised as high performance thermosetting resins for many industrial applications but unfortunately some are characterised by a relatively low toughness. In this respect, many efforts have been made to improve the toughness of cured epoxy resins by the introduction of rigid particles, reactive rubbers, interpenetrating polymer networks and engineering thermoplastics within the matrix. In the present work liquid amine-terminated butadiene acrylonitrile (ATBN) copolymers containing 16% acrylonitrile is added at different contents to improve the toughness of diglycidyl ether of bisphenol A epoxy resin using polyaminoimidazoline as a curing agent. The chemical reactions suspected to take place during the modification of the epoxy resin were monitored and evidenced using a Fourier transform infrared. The glass transition temperature ( T g) was measured using a differential scanning calorimeter. The mechanical behaviour of the modified epoxy resin was evaluated in terms of Izod impact strength (IS), critical stress intensity factor, and tensile properties at different modifier contents. A scanning electron microscope (SEM) was used to elucidate the mechanisms of deformation and toughening in addition to other morphological features. Finally, the adhesive properties of the modified epoxy resin were measured in terms of tensile shear strength (TSS). When modifying epoxy resin with liquid rubber (ATBN), all reactivity characteristics (gel time and temperature, cure time and exotherm peak) decreased. The infrared analysis evidenced the occurrence of a chemical reaction between the two components. Addition of ATBN led to a decrease in either the glass transition temperature and stress at break accompanied with an increase in elongation at break and the appearance of some yielding. As expected, the tensile modulus decreased slightly from 1.85 to about 1.34 GPa with increasing ATBN content; whereas a 3-fold increase in Izod IS was obtained by just adding 12.5 phr ATBN compared to the unfilled resin. It is obvious that upon addition of ATBN, the Izod IS increased drastically from 0.85 to 2.86 kJ/m 2 and from 4.19 to 14.26 kJ/m 2 for notched and unnotched specimens respectively while K IC varies from 0.91 to 1.49 MPa m 1/2 (1.5-fold increase). Concerning the adhesive properties, the TSS increased from 9.14 to 15.96 MPa just by adding 5 phr ATBN. Finally SEM analysis results suggest rubber particles cavitation and localised plastic shear yielding induced by the presence of the dispersed rubber particles within the epoxy matrix as the prevailing toughening mechanism.

Effect of Hydroxyphenylmaleimide on the Curing Behaviour and Thermomechanical Properties of Rubber-Modified Polybenzoxazine

Hydroxyphenylmaleimide (HPMI) and/or amine terminated butadiene acrylonitrile (ATBN)-modified polybenzoxazine were prepared by mixing benzoxazine monomer (Ba), HPMI and ATBN. The onset of the ring opening of the pristine Ba started with differential scanning calorimetry at 223°C with a maximum at 247°C. The incorporation of ATBN lowered the onset and the maximum of the exotherm to 180°C and 216°C respectively. The incorporation of HPMI initiated the ring opening of Ba at a temperature as low as 160°C with a maximum at 200°C. Viscoelastic measurements showed that the incorporation of HPMI increased the Tg and the storage modulus compared to that of the unmodified polybenzoxazine and ATBN-modified polybenzoxazine. Tensile property measurements indicated that the tensile modulus was enhanced with the addition of HPMI to ATBN-modified polybenzoxazine accompanied with little decrease in the elongation at break. Thermogravimetric analysis showed that the addition of HPMI enhanced the thermal stability of polybenzoxazine.

Effects of Atbn Rubber Additions on the Fracture Toughness of Unsaturated Polyester Resin

Improvement to the fracture toughness of an unsaturated polyester resin and composites by the addition of amine terminated butadiene-acrylonitrile (ATBN) rubber has been investigated. Addition of 6pph ATBN rubber gave a modest gain in fracture toughness of the resin. Electron microscopy studies showed that large agglomerates of a mixture of the rubber and the base resin were formed rather than discrete droplets of the rubber, and this is considered to be the reason for the modest gain in fracture toughness. Unidirectional glass fibre reinforced composites, made with ATBN toughened resin, showed significant gains in inter-laminar fracture toughness. The increased inter-laminar fracture toughness of the rubber modified resin is considered to be due to a combination of localised bonding between rubber/resin agglomerates and the glass fibres, and the lower tensile strength and flexural modulus of the rubber modified resin.