Ethyl Butyl Acrylate Research Articles

Determination of solar optical properties of transparent polymer films using UV/vis spectroscopy

In this paper, 4- and 5-flux models were implemented and used for the determination of absorption and scattering coefficients of transparent polymer films by UV/vis/NIR spectroscopy. The models were applied for a systematic characterization of polar ethylene copolymer films in the solar radiation range. The investigated ethylene copolymer films were highly transparent in the solar range of radiation, with hemispheric transmittance values above 91% and hemispheric reflectance values of about 8%. Both models revealed a significant forward scattering behavior of the films. The 4-flux model fitted hemispheric and diffuse transmittance far better than the 5-flux model. Hemispheric reflectance values were overestimated by both models. Similar absorption coefficient values ranging from 0.4 to 0.6 cm −1 were obtained for all investigated films. While ethylene(acrylic acid/butylacrylate) terpolymer showed the lowest scattering coefficient (10.9 (5-flux) and 6.8 cm −1 (4-flux)), the highest scattering coefficient (26.2 (5-flux) and 35.2 cm −1 (4-flux)) was found for ethylene(butylacrylate) copolymer.

Thermostimulative shape‐memory effect of reactive compatibilized high‐density polyethylene/poly(ethylene terephthalate) blends by an ethylene–butyl acrylate–glycidyl methacrylate terpolymer

AbstractHigh‐density polyethylene (HDPE)/poly(ethylene terephthalate) (PET) blends were prepared by means of melt extrusion with ethylene–butyl acrylate–glycidyl methacrylate terpolymer (EBAGMA) as a reactive compatibilizer. The effects of the EBAGMA and PET contents, recovery temperature, and stretch ratio on the thermostimulative shape‐memory behavior of the blends were studied. The results show that the addition of EBAGMA to the HDPE/PET blends obviously improved the compatibility and the shape‐memory effects of the blends. The response temperature was determined by the melting point of HDPE, and the shape‐recovery ratio of the 90/10/5 HDPE/PET/EBAGMA blend reached nearly 100%. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

A TGA-FTIR study on the effect of CaCO 3 on the thermal degradation of EBA copolymer

The thermal degradation of ethylene–butyl acrylate (EBA) copolymer with/without CaCO 3 has been studied via the combined TGA-FTIR technique at a heating rate of 10 °C/min in high purified N 2. The volatiles from EBA on heating include mainly 1-alkene (i.e. 1-butene), hydrocarbon chain fragments, CO 2, butyl acrylate-containing fragment, as well as the trace of CO and H 2O in the temperature range of 350–500 °C. The 1-butene is most likely formed through ester pyrolysis. The two bands at 2925 cm −1 (asymmetric stretching of –CH 2 –, corresponding to hydrocarbon chain fragments), and 720 cm −1 (plane rocking of –CH 2–, representative of the alkanes with low molecular weight –(CH 2) n –, n ≥ 4) were indicative of the hydrocarbon species essentially accompanied with acrylate-containing fragments at high temperature. Based on the data message of the TGA and the Gram–Schmidt curves, it shows that the EBA copolymer becomes much more stable in the presence of CaCO 3. The volatiles involved in the pyrolysis of EBA copolymer have qualitatively chemical composition similar to the case with CaCO 3. Obviously, both the descending flammable volatiles and the ascending creation in CO 2 from EBA copolymer do come intimately from the interposition of CaCO 3. That both the prolonged ignition time and the reduced heat release rate of EBA during combustion depend, therefore, on the presence of CaCO 3 is being expected.

Stress induced cracks in carbon black filled elastomers probed by atomic force microscopy

In the current study, carbon black (CB) filled ethylene butylacrylate copolymer samples, which are submitted to a uniaxial creep, are probed with a sub-100-nm spatial resolution using atomic force microscopy in tapping mode. We demonstrate the significant effect of the long-time application of stress, at low strain amplitude well below the breaking threshold, on the crack occurrence along the interfaces between polymer and CB aggregates. The data analysis indicates a log-normal distribution of crack width whose average value follows an exponential saturation as a function of aging time. A possible model realizing this behavior is the rate dependent theory of fracture for polymers.

Influence of clays on the flame retardancy and high temperature viscoelastic properties of polymeric intumescent formulations

A natural Brazilian montmorillonite clay was submitted to organophilization treatments to evaluate the effect of these treatments on the flame retardancy potential of polymer composites containing an intumescent ammonium polyphosphate and pentaerythritol formulation. An ethylene–butyl acrylate copolymer was used as the polymer matrix. Natural or organophilic clays were added both to the pure polymer and to the polymer containing the intumescent mixture. The influence of these mineral fillers, and of their organophilization treatments, on flame retardancy was investigated by thermogravimetric analysis (TGA), limiting oxygen index (LOI), UL-94 rating standard, heating microscopy, rheological measurements and cone calorimetry. The results show that these inorganic additives have a synergistic effect on composites containing the intumescent formulation.

Morphology and image analysis of polymer modified bitumens

This paper presents a laboratory study of styrene butadiene styrene (SBS); ethylene vinyl acetate (EVA) and ethylene butyl acrylate (EBA) based polymer modified bitumen samples (PMBs). The PMBs have been produced by mixing a 50/70 penetration grade unmodified (base) bitumen with copolymers at different proportions. The fundamental characteristics of the PMBs have been determined using conventional methods. The morphology of the samples as well as the percent area distribution of polymers throughout the base bitumen have been characterized and determined by means of fluorescent light optic microscopy and Qwin-Plus image analysis software, respectively. The results indicate that the fundamental properties and morphology of the modified bitumens are dependent on the type of polymer and polymer content. Polymer modification improves the conventional properties of the base bitumen such as penetration, softening point, temperature susceptibility. At low polymer contents, the samples reveal the existence of dispersed polymer particles in a continuous bitumen phase, whereas at high polymer contents a continuous polymer phase is observed. Moreover it is found out that a relationship exists between the polymer content and percent area distribution of polymers.

Mechanical fatigue and dielectric relaxation of carbon black/polymer composites

Using a home-built experimental setup, we investigate the carbon black (CB) volume fraction-resolved, time-resolved, and frequency-resolved spectra of the room temperature (well above the glass transition temperature of the matrix) effective complex permittivity of well characterized CB filled ethylene butylacrylate copolymer samples that are submitted to a uniaxial tension. We focus here on three samples with CB volume fraction less, near, and well away the percolation threshold at about 8 vol %. Our primary observation is that the temporal evolution of the real and imaginary parts of the effective permittivity is distinctly different for samples containing a CB volume fraction below and above percolation threshold. For samples containing a CB volume fraction below and close to the percolation threshold, and at a given frequency, ε′ and ε″ remain constant over the time scale of our measurements. For the sample containing a CB volume fraction above the percolation threshold the evolution of ε′ and ε″ is different in the low and high elongation ratio regimes. At low strain, the temporal evolution of permittivity during aging under stress shows a logarithmic growth phase followed by a logarithmic decay phase, whereas for sufficiently large strain the permittivity behaviors coincide with those observed below the percolation threshold. To explain the issues involved, we argue that the phenomenology for physical aging in these materials is related to the change in the mesostructure, formed by the heterogeneous three-dimensional interconnected network of polymer and of aggregates (or agglomerates) of CB particles, as the composite is stretched. Indeed, it is possible to argue qualitatively that below the percolation threshold the time-independent permittivity behavior is reminiscent to the elasticity network properties of the polymeric matrix. The reorientation and breakdown of the CB aggregates are believed to be crucial for the physical aging understanding above the percolation threshold and low strain. An examination of the surface and volume morphological evolutions of these materials under the action of a mechanical stress at the microscale by scanning electron microscopy and atomic force microscopy indicates that aging during a few hundreds of hours, even at a moderate strain, generates voids and cracks that are aligned along the stretching direction. The overall behavior is compared to what occurs in another type of filled polymer system, i.e., plastoferrites, for which it was recently discovered that two characteristic time scales are required to describe physical aging.

Influence of uniaxial tension on the microwave absorption properties of filled polymers

The evolution of the frequency-dependent absorption spectra for plastoferrites and carbon black-filled ethylene butylacrylate copolymer composites subjected to a uniaxial tension is evaluated using a vector network analyzer as a function of the elongation ratio over the frequency range of 0.3–5 GHz and at room temperature. The absorption spectrum has a double-peaked structure with two broad and symmetrical components. The positions of the lower-frequency peak (1.5 GHz) and the higher-frequency (≅4±0.3 GHz) do not change with extension over the considered range of strain, however, their relative absorption energy changes versus tensile stress can be explained in terms of a Gaussian molecular network model (affine behavior) provided that the elasticity network in the material occurs in a manner that is topologically similar to the elasticity network of a conventional rubber. The sensitivity of the microwave absorption to elongation ratio can be exploited to provide artificially structured materials with tunable electromagnetic properties.

Toughening of recycled poly(ethylene terephthalate)/glass fiber blends with ethylene–butyl acrylate–glycidyl methacrylate copolymer and maleic anhydride grafted polyethylene–octene rubber

AbstractThe aim of this study was to improve the toughness of recycled poly(ethylene terephthalate) (PET)/glass fiber (GF) blends through the addition of ethylene–butyl acrylate–glycidyl methacrylate copolymer (EBAGMA) and maleic anhydride grafted polyethylene–octene (POE‐g‐MAH) individually. The morphology and mechanical properties of the ternary blend were also examined in this study. EBAGMA was more effective in toughening recycled PET/GF blends than POE‐g‐MAH; this resulted from its better compatibility with PET and stronger fiber/matrix bonding, as indicated by scanning electron microscopy images. The PET/GF/EBAGMA ternary blend had improved impact strength and well‐balanced mechanical properties at a loading of 8 wt % EBAGMA. The addition of POE‐g‐MAH weakened the fiber/matrix bonding due to more POE‐g‐MAH coated on the GF, which led to weakened impact strength, tensile strength, and flexural modulus. According to dynamic rheometer testing, the use of both EBAGMA and POE‐g‐MAH remarkably increased the melt storage modulus and dynamic viscosity. Differential scanning calorimetry analysis showed that the addition of EBAGMA lowered the crystallization rate of the PET/GF blend, whereas POE‐g‐MAH increased it. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

Melt rheological properties of reactive compatibilized HDPE/PET blends

AbstractMelt rheological properties of high density polyethylene and poly(ethylene terephthalate) (HDPE/PET) blends compatibilized by an ethylene–butyl acrylate–glycidyl methacrylate terpolymer (EBAGMA) were studied by means of a HAAKE torque rheometer and a capillary rheometer. The phase morphology of the blends was evaluated by a scanning electron microscope (SEM). The results showed that the melts of blends behave pseudoplasticity. The addition of EBAGMA strengthens the interfacial adhesion between HDPE and PET and improves the phase dispersion due to reactive compatibilization. It was observed that the balance torque, melt viscosity, and sensitivity of melt viscosity to shear rate of the melts increase with increasing content of EBAGMA, but the melt flow index and activation energy decrease. At the same time, the plasticizing time is shortened indicating that the processability of the compatibilized blends has been improved. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

Influence of the Structure of Acrylate Groups on the Flame Retardant Behavior of Ethylene Acrylate Copolymers Modified with Chalk and Silicone Elastomer

This study treats the flame retardant effects of different ethylene acrylate copolymers used in a chalk and silicone elastomer system, specifically the flame retardant chemistry and behavior at lower temperatures. The presence or absence of ester pyrolysis, formation of ionomers or other crosslinks, viscosity, and the effects of these factors on the formation and stability of the intumescent structure formed during heating are discussed. The effects of the acrylate content and melt flow rate in flame retardant compounds based on ethylene butyl acrylate copolymer and ethylene ethyl acrylate copolymer are examined. Results of oxygen index, cone calorimetry (including visual observations), dripping, viscosity measurement, thermogravimetric analysis, and infrared spectroscopy are reported.

Microwave dielectric properties of carbon black filled polymers under uniaxial tension

Broadband microwave spectroscopy is commonly employed in the determination of the wave transport properties in mesostructured polymers with embedded carbon black particles. However, very little is known on how uniaxial stress affects the effective permittivity of these percolative materials. In this work we carry out a comprehensive study of the complex permittivity spectra of carbon black filled ethylene butylacrylate copolymer which is submitted to a tensile stress up to 45% over the 0.1−3 GHz frequency range and at room temperature. Permittivity measurements indicated large decreases in the real and imaginary parts of the effective permittivity of the axially elongated samples. This set of experiments illustrates that these microwave permittivity data scale as a power law in frequency, where the exponent is strongly sensitive to stress. In addition, we show that our effective permittivity measurements under stress can be explained in terms of the Gaussian molecular network model in the limit of low stress. The observed variation of the effective permittivity is consistent with that reported for related materials, i.e., carbon black filled cross-linked rubber. Our analysis points out to the importance of local properties, i.e., properties associated with specific subsystems (e.g., aggregates of carbon black particles) in understanding the effective dielectric properties of these “macroscopic homogeneous” materials. Improved reliability through real-time monitoring of strain and material parameters (permittivity and permeability) simultaneously will result in significant benefits to the community in many areas, such as aerospace, power, and automotive industries.

Rheological investigation of the influence of acrylate polymers on the modification of asphalt

AbstractThe effect of ethylene, ethylene acrylate and glycidyl methacrylate (EA) terpolymer, and ethylene butyl acrylate (EBA) copolymer on asphalt modification was investigated at 4, 6 and 8% polymer concentrations. Both melt state rheology and asphalt concrete mix (ACM) were investigated. In the melt state analysis, dynamic shear rheology, storage stability, artificial ageing, and performance grading (PG) were studied. The PG grading of polymer modified asphalt (PMA) is correlated to the elastic properties of the polymers. Both resins improved the rheological properties, reduced the temperature susceptibility, showed better storage stability, and increase the upper grading (performance) temperature of the base asphalt. The two polymers showed similar ageing characteristics with little influence on flow activation energy. In asphalt concrete mix analysis, Marshall stability, stripping (durability), resilient modulus, and permanent deformation tests were performed. Polymer‐modified asphalt concrete mix (PMACM) has increased percent retained stability and the resilient modulus when compared with ACM. The elastic modulus of PMA and the resilient modulus of their ACM followed the same trend. Weak influence on water sensitivity was observed, but excellent rutting resistance was obtained for PMACM over ACM. EA (much cheaper than EBA) produced satisfactory properties of PMA and superior ACM properties when blended with the high asphaltenes Arabian asphalt. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 3446–3456, 2006

Ethylene Butyl Acrylate Glycidyl Methacrylate Terpolymer as an Interfacial Agent for Isotactic Poly(propylene)/Wood Flour Composites

AbstractSummary: This paper presents the results of an experimental investigation concerning the use of an ethylene butyl acrylate and glycidyl methacrylate (EBAGMA) terpolymer as an interfacial agent for isotactic poly(propylene)/wood flour (iPP/WF) composites at various filler ratios (10, 20 and 30 wt.‐%). The effects of the EBAGMA terpolymer on the morphology, tensile properties, impact strength and water uptake of the iPP/WF composites were studied and the results were compared with those obtained with maleated poly(propylene) (MAPP) used as a compatibilizer. Initially, the mixing process was performed in a calendaring unit at 170 °C for pre‐homogenization of the filler in the matrix. Composites made out of these combinations were then ground and injected into a standard mold at 180 °C in the absence and the presence of compatibilizer. The results indicated that both EBAGMA terpolymer and MAPP improved the interactions between iPP and WF, and induced a better dispersion of wood particles in the polymer matrix, as revealed by scanning electron microscopy (SEM). Furthermore, tensile properties and impact strength were also increased. Another important effect was on the water absorption property, which was significantly lower for the samples with EBAGMA and MAPP. However, EBAGMA terpolymer produced better enhancement of the properties of the iPP/WF composites compared to the compatibilized samples with MAPP.SEM micrographs of the fracture surface of iPP/WF composites (70/30 wt.‐%): (a) without compatibilizer; (b) with 10 pph EBAGMA; (c) with 10 pph MAPP. Magnification was ×500.magnified imageSEM micrographs of the fracture surface of iPP/WF composites (70/30 wt.‐%): (a) without compatibilizer; (b) with 10 pph EBAGMA; (c) with 10 pph MAPP. Magnification was ×500.

Toughening modification of PBT/PC blends with PTW and POE

AbstractNew toughened poly(butylene terephthalate) (PBT)/bisphenol A polycarbonate (PC) blends were obtained by melt blending with ethylene–butylacrylate–glycidyl methacrylate copolymer (PTW) and ethylene‐1‐octylene copolymer (POE) in a twin‐screw extruder. The mechanical properties of PBT/PC blends were investigated. The presence of PTW or POE could improve the mechanical properties except for the tensile strength and flexural properties of the PBT/PC blends. However, a combination use of PTW and POE had a strong synergistic effect, leading to remarkable increases in the impact strength, elongation at break, and Vicat temperature and some reduction of the tensile strength and flexural properties. The relationship between mechanical properties and morphology of the PBT/PC/PTW/POE blends was studied. The morphology was observed by scanning electron microscopy and the average diameter of dispersed phase was determined by image analysis, and the critical interparticle distance for PBT/PC was determined. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 54–62, 2006

PLastic Films for Agricultural Applications

The most important agricultural applications of plastic films are greenhouse, walk-in tunnel and low tunnel covers, and mulching. The raw materials are usually low density polyethylene (LDPE) and ethylene-vinyl acetate (EVA) or ethylene-butyl acrylate (EBA) copolymers for the covers and linear low density polyethylene (LLDPE) for mulching. The market is explosively growing in China, and slowly growing in the rest of the world. The key properties for these applications are durability, optical (ultraviolet, visible, near infrared, and middle infrared) properties, and the antidrip or antifog effect. Recent developments in this area include UV-blocking, NIR-blocking, fluorescent, and ultrathermic films.

Toughening modification of PBT/PC blends by PTW

Poly(butylene terephthalate)(PBT)/polycarbonate(PC)/ethylene–butylacrylate–glycidyl methacrylate (PTW) blends containing PTW as toughening modifier were obtained by extrusion and injection molding. The mechanical properties of the PBT/PC/PTW blends were investigated. The results showed that the addition of PTW led to great increases in the impact strength, elongation at break, Vicat temperature and a reduction in the tensile strength and flexural properties of PBT/PC blends. The blend morphology was observed by scanning electron microscopy and the dispersed phase average diameter was determined by image analysis. The relation between the impact resistance and the phase morphology was discussed, and the critical ligament size for PBT/PC was determined.

Scaling of the viscoelasticity of highly filled carbon black polyethylene composites above the melting point

Different types of linear low-density polyethylene and ethylene butylacrylate copolymers were mixed with various types of carbon black in amounts between 25 and 40% by weight. Viscoelastic properties were measured using dynamic mechanical analysis applying a frequency sweep. Typically, the complex modulus approaches asymptotically a constant value at small frequencies, which is referred to as ‘yield modulus’. These results were analysed using a scaling approach according to which the complex modulus and the frequency are normalised by the yield modulus and the quotient of the yield modulus and the polymer viscosity, respectively. Thus a master curve is achieved for nearly all samples independent of the polymer and carbon black type and loading. A similar scaling behaviour has been observed earlier for differently concentrated suspensions of carbon black in Newtonian liquids, but not for filled polymers and different carbon blacks. Thus, contributions from polymer and carbon black to the compounds' viscoelastic properties are discussed.

Compatibilization of Poly(propylene)/Polyamide 6 Blends with Functionalized Poly(propylene)s Prepared with Metallocene Catalyst

AbstractSummary: Propylene was copolymerized with 10‐undecen‐1‐ol using dimethylsilanylbis(2‐methyl‐4‐phenyl‐1‐indenyl)zirconium dichloride as catalyst and MAO and TIBA as cocatalysts. Comonomer incorporations from 0.1 to 0.9 mol‐% (0.5 to 3.6 wt.‐%) were obtained. These hydroxyl functionalized copolymers were applied as compatibilizers to PP/PA6 blend with a composition of 70/30. For comparison, hydroxyl functionalized polyethylene prepared with metallocene catalyst and commercial MAH grafted ethylene butyl acrylate (E/BA/MAH) and poly(propylene) (PP‐g‐MAH) were also used as compatibilizers. Effects of the compatibilizers on morphology and mechanical and thermal properties of the blends were studied. Enhanced adhesion between the blend components was observed in morphology and dynamic mechanical studies. Although improvement in toughness was not as pronounced as expected, there were indications that the hydroxyl functionalized propylene copolymers prepared with metallocene catalysts could serve as a new type of compatibilizer in polymer blends.SEM micrograph (5 000×) of an PP/PA6/PP‐co‐OH4 blend.magnified imageSEM micrograph (5 000×) of an PP/PA6/PP‐co‐OH4 blend.

Multiple threshold percolation in polymer/filler composites

Local variations in filler particle concentration and/or shape and orientation in static filler/polymer composites are modelled as distributions of percolation thresholds. The concentration variations can be due to insufficient mixing, formation of semicrystalline voids during cooling from the melt, shrinkage during polymer curing, flow during physical compression or the like. Irregular filler shapes, especially elongated shapes, reduce the percolation threshold; thus, natural variations in the shapes and orientations of filler particle aggregates lead to locally varying percolation thresholds. A distribution of percolation thresholds leads to an apparent average percolation threshold based on the conductivity below the mean percolation threshold. For filler concentrations above the apparent percolation threshold, the dielectric constant continues to increase before reaching a lowered peak value at the mean percolation threshold and then decreasing. This can explain some ‘anomalous’ published experimental results concerning the dielectric constant just above the percolation threshold. In the frequency plane, the percolation threshold distribution can lead to a slight reduction of the apparent critical exponents x and y of the frequency dependencies of the conductivity and relative dielectric constant, respectively. Our experimental results on ethylene butylacrylate copolymer/carbon black composites support the theory.