Fabrication and characterization of olive pomace filled PP composites

Accepted Manuscript Fabrication and characterization of olive pomace filled PP composites N. Kaya, M. Atagur, O. Akyuz, Y. Seki, M. Sarikanat, M. Sutcu, M.O. Seydibeyoglu, K. Sever PII:

S1359-8368(17)30825-9

DOI:

10.1016/j.compositesb.2017.08.017

Reference:

JCOMB 5242

To appear in:

Composites Part B

Received Date: 7 March 2017 Revised Date:

21 July 2017

Accepted Date: 28 August 2017

Please cite this article as: Kaya N, Atagur M, Akyuz O, Seki Y, Sarikanat M, Sutcu M, Seydibeyoglu MO, Sever K, Fabrication and characterization of olive pomace filled PP composites, Composites Part B (2017), doi: 10.1016/j.compositesb.2017.08.017. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

ACCEPTED MANUSCRIPT Fabrication and characterization of Olive Pomace filled PP composites N.Kayaa, M.Atagurb, O.Akyuza, Y.Sekic, M.Sarikanatd, M.Sutcub, M.O.Seydibeyoglub, K.Severe. İzmir Katip Çelebi University, Institude of Science, Material Sience and Engineering Department, Çiğli, İzmir,.TURKEY İzmir Katip Çelebi University, Engineering and Architecture Faculty, Material Sience and Engineering Department, Çiğli, İzmir,.TURKEY c

Dokuz Eylül University, Science Faculty, Chemistry Department, Buca, İzmir,.TURKEY d

e

RI PT

b

Ege University, Engineering Faculty, Mechanical Engineering Department, Bornova, İzmir,.TURKEY

İzmir Katip Çelebi University, Engineering and Architecture Faculty, Mechanical Engineering Department, Çiğli, İzmir,.TURKEY

M AN U

ABSTRACT

SC

a

The aim of this study is to investigate the filling properties of an agricultural waste, olive pomace powder (OP), for polypropylene (PP) matrix material. Different weight fractions of OP (from 10 to 40 wt %), which has a median particle size of 21.36 µm (D50) µm, were

TE D

loaded into PP by high-speed thermo kinetic mixer. In this research, the effects of weight fraction of OP within PP on mechanical, viscoelastic, thermal, chemical, crystallographic, and morphological properties of PP composites were investigated by tensile and three point

EP

bending test, dynamic mechanic analysis, thermogravimetric analysis and differential scanning calorimetry, Fourier transform infrared analysis, X-ray diffraction analysis, and

AC C

scanning electron microscopy. When 40wt% OP filler was loaded into PP, the Young’s modulus and flexural modulus of PP increased by about 62.5% and 19%, respectively. The storage modulus and thermal stability of PP were remarkably enhanced with increasing OP weight fraction.

Keywords: olive pomace, mechanical properties, thermal properties

ACCEPTED MANUSCRIPT 1.

INTRODUCTION

Along with the fast growing developments in polymeric materials, the need for green and sustainable materials is ever increasing very fast [1-3]. As the new concept of “Circular

RI PT

Economy” states, utilization of the products in a circular and recycling way is very critical [4]. Moreover, the industry revolution 4.0 also strongly states that the using of sustainable materials is very important for a better environment [5]. The increased use of biocomposites

SC

and eco-friendly composites is very important for the developing countries as the agricultural products more produced bring wealth to rural areas [6]. Biocomposites utilize many industrial

M AN U

agricultural fiber in the form either reinforcement or filler in polymer materials [7-16]. Within the context of circular economy, the utilization of plant residues and agricultural fibers play a key role for green composites and affordable materials. From the engineering perspective, besides creating novel materials, the production method should be also cost effective. Circular economy tries to utilize the side product of many industrial products in a

TE D

value added application. Agricultural wastes are generally incinerated to obtain energy. However, these side products can be easily utilized in polymer matrices to create much more

EP

wealth and eco-friendly materials [17-18].

For agricultural wastes and fibers, each country tries to utilize the plants that grow in their

AC C

land. Mediterranean area is full of olive trees and olive plants. Olive is quite healthy and has many benefits for the human body [19]. It is consumed in large quantities in Italy, Greece, France, and Turkey. As people consume olive, the olive stone is not considered as a product for polymer matrices. Especially, there are big olive oil manufacturers in Aegean region and the olive pomace (OP) and olive stone arise in large quantities. The farmers are trying to find suitable application areas for these OP materials to obtain value added products. In this study, OP powder, which was obtained from olive oil producers, was mixed with polypropylene (PP) in order to obtain new green composites by using melt mixing techniques.

ACCEPTED MANUSCRIPT This study aims to demonstrate that whether OP, the side products of the olive industry, can be utilized in a novel polymer composite or not.

2.

MATERIALS AND METHODS

2.1. Materials

RI PT

The matrix material PP (MH 418) having a density of 0.90 g/cm3 and a melt flow index of 5 g/10 min was supplied from Petkim-SOCAR–Turkey. OP was obtained from Altan olive oil factory (Saruhanlı-Manisa in Turkey). Then, OP was ground with a laboratory grinder (Retsch

SC

RS 200 vibratory disc mill). Then, particles were passed through a 100 mesh sieve (particles

M AN U

smaller than 0.150 mm) and dried at 70 °C for 48 h to remove moisture. 2.2. Characterization OP Powder Sample

The particle size distribution of OP powders was analyzed by a laser particle size analyzer (Mastersizer 2000, Malvern) in water as a dispersant. Sonic pulse was applied to dispersant in

TE D

the course of measurement. X-ray diffraction (XRD) analysis of OP powder sample was performed using a Panalytical Emperian model (with CuKα radiation at 45 kV and 40 mA).

EP

2.3. Manufacturing of Composite Materials

AC C

PP matrix composites at various weight fractions with 10, 20, 30, and 40% of OP (PP-10OP, PP-20OP, PP-30OP, and PP-40OP, respectively) were produced by using a laboratory type high-speed thermo kinetic mixer. In order to produce OP filled PP compound, a blend of OP and PP at about 70 g was processed in the mixer at 2000 rpm. The composite plates were produced by the help of hydraulic hot and cold press at 170 ºC for 210 s between 40-120 bar pressure in hot press, then composite plates were cooled at 20 °C for 120 s at 120 bar pressure in cold press.

ACCEPTED MANUSCRIPT 2.4. Characterization of Composite Materials

Tensile tests were performed by using a universal testing machine having a 5-kN load cell (Shimadzu Autograph AG-IS, Japan). The tensile tests of the composites were carried out according to the ASTM D-638 standard, and the crosshead speed was selected to be 50

RI PT

mm/min. The tests were repeated at least five times for each type of composite to check for repeatability. The flexural strength and modulus of the composites were determined using a three-point bending test according to the ASTM D-790 standard. The tests were conducted

SC

with the universal testing machine using a crosshead speed of 1 mm/min and a span length of 32 mm. The tests were repeated at least five times. The dynamic mechanical analysis (DMA)

M AN U

of PP and OP filled composites was carried out on a Dynamic Mechanical Analyzer (TA Instruments Inc., DMA Q800). The storage and loss moduli of PP and its composites were determined. Single cantilever was used and multi frequency-strain modulus mode was selected to analyze all specimens between the temperatures of 25 and 140 °C in air

TE D

atmosphere. Differential Scanning Calorimetry (DSC) analysis was conducted by using differential scanning calorimeter (TA Instrument Q2000). In order to erase the thermal history, the samples were firstly heated to 200°C at a heating rate of 10°C/min and held for 3

EP

min. Then the samples were cooled to 90°C and held 1 min. Afterwards, the samples were

AC C

heated to 190°C at a heating rate of 10°C/min. FTIR analysis was conducted by using Fourier Transform Infrared Spectrometer (Thermo 50i) in attenuated total reflection (ATR) mode. FTIR spectra, which are ranged between 4.000–650 cm−1, were recorded with a resolution of 4 cm−1 and with an accumulation of 16 scans. Thermal stabilities of samples were investigated by Thermogravimetric analysis (TGA) using a STA 8000 instrument from Perkin Elmer. The samples were heated from room temperature to 600°C at a heating rate of 10°C/min under nitrogen atmosphere. X-ray diffraction (XRD) analysis was performed using a Panalytical Emperian model (with CuKα radiation at 45 kV and 40 mA) to determine the characteristic

ACCEPTED MANUSCRIPT peaks of the raw materials and the crystallinity of the produced composites. The fracture surfaces of the composites were observed using a scanning electron microscope (SEM) (Carl Zeiss 300VP, Germany) operated at 2.5 kV. A thin layer of gold was coated on the fractured

extent of sample arcing during SEM observation.

3.

RESULTS AND DISCUSIONS

SC

3.1. Particle Size Analysis

RI PT

surface of the composites by using an automatic sputter coater (Emitech K550X) to reduce the

Particle size distribution of OP is shown in Figure 1. According to the Figure 1, the particle

M AN U

volume distribution of OP powder sample shows a gauss distribution. The mean size of powders is 21.36 µm (D50) based on a volume distribution and 50% of the particles are smaller than 21.36 µm. Besides, D10 and D90 were obtained to be 4.28 µm and 58.47 µm, respectively. The curve also shows the presence of some particles smaller than 1 µm and

3.2. Tensile Testing

TE D

larger than 100 µm.

Figure 2 shows the effect of filler weight fraction on the tensile properties such as tensile

EP

strength and Young’s modulus of PP and OP filled PP composites. As shown in Figure 2,

AC C

tensile strength and Young's modulus values of PP were obtained to be 35.2 and 893 MPa, respectively. The tensile strength of PP composites containing OP filler was lower than that of PP. Moreover, the tensile strength of the composites decreased with increasing P weight fraction up to 40%. It is observed that after incorporation of OP into PP, tensile strength of PP decreased from 35.2 to 18.4 MPa. Fillers having an irregular shape do not contribute to the stress transferred to the polymer matrix. In this manner, the incorporated material acts as a filler rather than a reinforcement [20]. The decrease in tensile strength of composite compared to virgin polymer can be associated with inadequate wetting of the filler with the matrix, poor

ACCEPTED MANUSCRIPT dispersion of fillers, presence of agglomerates, and poor adhesion between the filler and matrix [21-22].

It can be also seen that the Young’s modulus of the PP increases with the addition of OP filler

RI PT

into PP in the studied weight fraction range (10, 20, 30, and 40%). Shumigin et al. point out that the Young’s modulus of the filler is higher than the that of the matrix material and this case leads to an increase in Young’s modulus of PP. Increased Young’s modulus of

SC

composites can be due to the restricted macromolecular mobility and deformability in the presence of filler particles [21]. When 40wt% OP filler was added into PP, the Young’s

M AN U

modulus of PP increased by 62.5%. In general, particle fillers are more rigid compared to the polymer matrix so filler addition causes an increase in the rigidity of the polymer matrix [22]. It can be said that with increasing the weight fraction OP filler in PP, PP become stiffer.

3.3. Three Point Bending Test

TE D

Figure 3 shows the effect of filler weight fraction on the flexural strengths and moduli of PP and OP filled PP composites. As illustrated in Figure 3, the flexural strength values of the composites were lower than that of PP. Moreover, flexural strength decreased continuously

EP

from 58.49 MPa for neat PP to 48.49 MPa, 39.82MPa, 37.84 MPa, and finally to 33.93 MPa

AC C

for 10, 20, 30, and 40% filler weight fractions, respectively. In Figure 3, it can be seen that, the flexural modulus of OP filled PP composites enhanced with an increase in filler loading. The highest flexural modulus value was obtained to be 2160.3 MPa for PP-40P. Moreover, the flexural modulus of the PP-40OP composite was approximately 19% higher than that of PP. The reasons for these behaviors can be explained using the same reasons as previously mentioned above.

ACCEPTED MANUSCRIPT 3.4. Dynamic Mechanical Analysis (DMA) Analysis

Viscoelastic properties of PP and OP filled PP composites were investigated by DMA technique. Variation of storage and loss modulus of PP and OP filled PP composites as a

RI PT

function of temperature is shown in Figure 4. DMA results indicate that the storage modulus values of OP filled PP composites are higher than that of PP at the whole temperature range. This point outs that the stiffness of OP filled PP composites is increased with the addition of

SC

OP particles.

The storage modulus values are also tabulated in Table 1. DMA results show that 10, 20, 30,

M AN U

and 40 wt% OP fillings into PP led to 10.6%, 15.4%, 28.9%, and 54.7% increases in storage modulus, respectively, when compared to that of PP at 30°C. The increase in storage modulus was due to mechanical limitation posed by increasing filler content embedded in the viscoelastic polymer matrix. It can also be seen from Table 1 that with increasing

TE D

temperature, the storage modulus values of OP filled PP composites decreased due to the softening of the matrix and initiation of the relaxation process [23].

EP

The retention ratio is known as the ratio of the storage modulus at 130°C to that at 30°C. The retention ratios of PP, PP-10OP, PP-20OP, PP-30OP, and PP-40OP were obtained to be 0.18,

AC C

0.20, 0.19, 0.21, and 0.22, respectively. It can be seen from the retention ratios that the OP filled PP composites possess improved mechanical properties compared to PP at high temperatures.

The variation of the loss modulus, E″, of the PP and OP filled PP composites against temperature are presented in Figure 4. Loss modulus represents energy loss as heat or molecular rearrangements during the loading cycle, which indicates the viscous nature of the polymer [24-25]. As shown in Figure 4, the loss modulus of composite with 10 wt% OP was

ACCEPTED MANUSCRIPT almost close to PP at low temperature. However, the loss modulus of composite with 10 wt% OP was much higher than that of PP at high temperature. On the other hand, the loss modulus of composites with 20, 30 and 40 wt% OP was much higher than that of PP in the whole

RI PT

temperature range.

The relaxation transition peak presented in Figure 4 represents the transition region from the glassy state to the rubbery state [25]. α relaxation peaks of PP, PP-10OP, PP-20OP,PP-30OP,

SC

and PP-40OP composites were obtained to be at 66.2, 69.5, 68.2, 71.9, and 73.7°C, respectively. It can be noted α relaxation peak of PP was increased with increasing the weight

M AN U

fraction of OP into PP.

3.5. Differential Scanning Calorimetry (DSC) Analysis

DSC curves of PP and OP filled PP composites are shown in Figure 5. DSC melting and crystallization parameters for PP and its composites such as melting temperature (Tm),

TE D

crystallization temperature (Tc), crystallization enthalpy (∆Hc), melting enthalpy (∆Hm), and the degree of super-cooling (∆T), are presented in Table 2. The degree of crystallinity (Xc) of PP composites was estimated using equation (1) [26]

EP

∆H m / φ PP x100 ∆H m0

(1)

AC C

X c (%) =

where ∆H°m is the melting enthalpy of 100% crystalline PP assumed to be (209J/g) and φPP is PP weight fractions in the composite [27]. Table 2 shows that the melting temperatures of PP slightly changed after the incorporation of OP, which indicates that the crystal size of PP did not change considerably. Besides, OP filling into PP improved the crystallization of PP because of the fact that the crystallization temperature enhanced by 2-3°C. As can be seen from Table 2, OP adding increased the

ACCEPTED MANUSCRIPT degree of crystallinity of PP by 4-8%. PP-20OP exhibited the greatest crystallinity in the composite samples. The super-cooling was decreased by filling of OP, which can be explained by the fact that filling of OP into PP enhanced the rate of crystallization of PP.

RI PT

3.6. Thermogravimetric Analysis (TGA) TGA curves of PP and OP filled PP composites can be seen in Figure 6. The results obtained from TG curves for the samples are summarized in Table 3. As can be seen from Table 3,

SC

there are two decomposition steps in the OP filled PP composites. First one is due to OP decomposition and the second one is due to PP decomposition. From TG curves, the

M AN U

decomposition temperatures at 5 % mass losses for PP, PP-10OP, PP-20OP, PP-30OP, and PP-40OP were determined to be 382, 381, 306, 308, and 282°C, respectively. 10wt% OP filling into PP did not affect the decomposition temperature of PP at 5% mass loss. However 40 wt% OP loading decreased the temperature by 100°C. Initial and maximum decomposition

TE D

temperatures of PP were considerably increased by filling of OP into PP. The initial and maximum decomposition temperature of PP was obtained to be 420 and 453°C respectively. 20 wt% OP filling into PP increased the initial and maximum decomposition temperatures to

EP

445 and 464°C, which indicates increases of 25 and 11°C, respectively. The residual weight values at 600°C for PP, PP-10OP, PP-20OP, PP-30OP, and PP-40OP were obtained to be

AC C

99.8, 95.6, 80.2, 68.2, and 58.3%, respectively. Filling of OP into PP increased the remaining residues due to charring of OP. It can be noted that char yield which is related with material flame resistance was increased by OP filling into PP. This may be due to the ring structures of cellulose and phenolic structures of lignin having greater char yield [28-29]. From TGA analysis, it can be claimed that the thermal stability of PP was markedly improved by filling of OP into PP.

ACCEPTED MANUSCRIPT 3.7. X-Ray Diffraction (XRD) Analysis The XRD pattern of OP powder is shown in Figure 7. From the pattern, it can be reported that OP powder sample has a characteristic peak of cellulose (2θ=22.5°). This residue includes

RI PT

amorphous and some crystalline phases such as quartz and calcium carbonate.

The XRD patterns of PP and OP filled PP composites show a number of characteristic peaks due to their crystalline structure, as shown in Figure 8. According to the result, PP has an

SC

isotactic polypropylene crystal structure. The results show that the filling of OP into PP has some effects on the crystallinity of the PP, as seen from Figure 8a. The lower peak intensities

M AN U

for the composites as compared to PP imply decreasing the crystallinity of the composite. Furthermore, the lowest intensity values in PP-40OP composite is due to presence of amorphous OP powder in the PP matrix and reduced crystallinity of composites. It can be seen from Figure 8 that the peak intensity of PP at 28.5° disappeared with increasing up to

TE D

40%OP addition. The peaks at about 26.6 and 29.3°, which are due to quartz and calcite within OP, can be seen in the diffraction pattern of the composite samples. This proves the existence of OP within the composites.

EP

3.8. Fourier Transform Infrared (FTIR) Analysis

AC C

FTIR spectra for PP and its composites are seen in Figure 9. The peak at 1623 cm-1 in the spectra of OP was observed due to carboxyl groups present in the components of composites [30]. Besides, the band at 1030 cm-1 in the spectrum OP probably corresponds to C-O groups of lignin, hemicelluloses, and cellulose components in composites [30]. As can be seen from Figure 9, the peaks at about 1620 cm-1 in the spectra of composites exhibited the availability of OP within the composite. Additionally, one of the prominent variations in the spectra of PP and its composites is the existence of the peaks at about 1030 cm-1 in the spectra of OP filled

ACCEPTED MANUSCRIPT composites. It can be reported that the FTIR spectra of composites confirm the presence of OP within PP matrix material. 3.9. Scanning Electron Microscopy (SEM) Analysis

RI PT

Fracture surfaces of PP containing OP are shown in Figure 10. It can be seen from Figure 10 that fillers left from the matrix after the tensile tests. Cavities were observed throughout the matrix. The result indicated a poor interfacial bonding between OP filler and PP matrix. The

SC

stress cannot be efficiently transferred from the matrix to the fillers. Thus, tensile and flexural strengths of the composites decreased. Orientation of PP matrix after fracture exhibited

M AN U

similarities in the direction of matrix in PP-10OP and PP-20OP composites, but matrix fracture of PP-30OP and PP-40OP composites seems to be omnidirectional. This irregularity could be attributed to demonstrating lower matrix strength under stress. Mechanical test

TE D

results were obtained to be in harmony with the SEM images of composites.

4. Conclusion

The production and characterization of OP filled PP composites were carried out in this study.

EP

The main conclusions obtained from this study are as follows:

AC C

• Tensile and flexural strengths of the composites decreased as the filler loading increased. However Young's modulus and flexural modulus increased with increasing filler loading.

• The crystallinity of PP increased with increase of OP loading into PP. The supercooling decreased by filling of OP because of the fact that filling of OP into PP enhanced the rate of crystallization of PP.

ACCEPTED MANUSCRIPT • The storage modulus of PP increased with increasing OP weight fraction in the whole temperature range. The loss modulus of 10 wt %OP was almost close to PP at low temperature. On the other hand, the loss modulus of the composite with 10 wt% OP was much higher than that of PP at high temperature. OP filled PP composites possess

RI PT

improved mechanical properties compared to PP at high temperatures.

• Maximum decomposition temperatures of PP were remarkably increased by filling of OP into PP.

SC

• This study demonstrated that that OP, the side products of the olive industry, can be

M AN U

utilized as a filler material for polypropylene matrix material.

Acknowledgements

TE D

Financial support for this study was provided by TUBITAK-The Scientific and Technological

References

EP

Research Council of Turkey, Project Number: 214M350

AC C

[1] Ku H, Wang H, Pattarachaiyakoop N, Trada M. A review on the tensile properties of natural fiber reinforced polymer composites. Compos Part B-Eng. 2011;42(4):856-73. [2] George J, Sreekala MS, Thomas S. A review on interface modification and characterization of natural fiber reinforced plastic composites. Polym Eng Sci. 2001;41(9):1471-85. [3] Kilinc AC, Atagur M, Ozdemir O, Sen I, Kucukdogan N, Sever K, et al. Manufacturing and characterization of vine stem reinforced high density polyethylene composites. Compos Part B-Eng. 2016;91:267-74. [4] Delgado-Aguilar M, Tarres Q, Pelach MA, Mutje P, Fullana-i-Palmer P. Are Cellulose Nanofibers a Solution for a More Circular Economy of Paper Products? Environ Sci Technol. 2015;49(20):12206-13. [5] Stock T, Seliger G. Opportunities of Sustainable Manufacturing in Industry 4.0. Proc Cirp. 2016;40:536-41. [6] Srinivasan P, Sarmah AK, Smernik R, Das O, Farid M, Gao W. A feasibility study of agricultural and sewage biomass as biochar, bioenergy and biocomposite feedstock: Production, characterization and potential applications. Sci Total Environ. 2015;512:495-505. [7] Mohanty AK, Misra M, Hinrichsen G. Biofibres, biodegradable polymers and biocomposites: An overview. Macromol Mater Eng. 2000;276(3-4):1-24.

ACCEPTED MANUSCRIPT

AC C

EP

TE D

M AN U

SC

RI PT

[8] Faruk O, Bledzki AK, Fink HP, Sain M. Biocomposites reinforced with natural fibers: 2000-2010. Prog Polym Sci. 2012;37(11):1552-96. [9] Kumar N, Mireja S, Khandelwal V, Arun B, Manik G. Light-weight high-strength hollow glass microspheres and bamboo fiber based hybrid polypropylene composite: A strength analysis and morphological study. Composites Part B: Engineering. 2017;109:277-85. [10] Georgiopoulos P, Christopoulos A, Koutsoumpis S, Kontou E. The effect of surface treatment on the performance of flax/biodegradable composites. Composites Part B: Engineering. 2016;106:88-98. [11] Scalici T, Fiore V, Valenza A. Effect of plasma treatment on the properties of Arundo Donax L. leaf fibres and its bio-based epoxy composites: A preliminary study. Composites Part B: Engineering. 2016;94:167-75. [12] Johnson S, Kang L, Akil HM. Mechanical behavior of jute hybrid bio-composites. Composites Part B: Engineering. 2016;91:83-93. [13] Sullins T, Pillay S, Komus A, Ning H. Hemp fiber reinforced polypropylene composites: The effects of material treatments. Composites Part B: Engineering. 2017;114:15-22. [14] Yan L, Chouw N, Jayaraman K. Flax fibre and its composites – A review. Composites Part B: Engineering. 2014;56:296-317. [15] El-Sabbagh A, Steuernagel L, Ziegmann G, Meiners D, Toepfer O. Processing parameters and characterisation of flax fibre reinforced engineering plastic composites with flame retardant fillers. Composites Part B: Engineering. 2014;62:12-8. [16] Chai MW, Bickerton S, Bhattacharyya D, Das R. Influence of natural fibre reinforcements on the flammability of bio-derived composite materials. Composites Part B: Engineering. 2012;43(7):286774. [17] Sahoo S, Seydibeyoglu MO, Mohanty AK, Misra M. Characterization of industrial lignins for their utilization in future value added applications. Biomass Bioenerg. 2011;35(10):4230-7. [18] Seydibeyoglu MO, Misra M, Mohanty A, Blaker JJ, Lee KY, Bismarck A, et al. Green polyurethane nanocomposites from soy polyol and bacterial cellulose. J Mater Sci. 2013;48(5):2167-75. [19] Pérez-Jiménez F, Ruano J, Perez-Martinez P, Lopez-Segura F, Lopez-Miranda J. The influence of olive oil on human health: not a question of fat alone. Molecular nutrition & food research. 2007;51(10):1199-208. [20] Magalhães WLE, Pianaro SA, Granado CJF, Satyanarayana KG. Preparation and characterization of polypropylene/heart-of-peach palm sheath composite. Journal of Applied Polymer Science. 2013;127(2):1285-94. [21] Shumigin D, Tarasova E, Krumme A, Meier P. Rheological and Mechanical Properties of Poly(lactic) Acid/Cellulose and LDPE/Cellulose Composites. Mater Sci-Medzg. 2011;17(1):32-7. [22] Reyes JEP. Effect of Surface Treatment and Particle Loading on the Mechanical Properties of CFB Fly Ash Reinforced Thermoset Composite. International Journal of Chemical Engineering and Applications. 2015;6(1):6. [23] Huang R, Xu X, Lee S, Zhang Y, Kim B-J, Wu Q. High density polyethylene composites reinforced with hybrid inorganic fillers: morphology, mechanical and thermal expansion performance. Materials. 2013;6(9):4122-38. [24] Greene JP, Wilkes JO. Steady-State and Dynamic Properties of Concentrated Fiber-Filled Thermoplastics. Polym Eng Sci. 1995;35(21):1670-81. [25] Wang CB, Ying SJ. Thermal, Tensile and Dynamic Mechanical Properties of Short Carbon Fibre Reinforced Polypropylene Composites. Polym Polym Compos. 2013;21(2):65-71. [26] Cheewawuttipong W, Fuoka D, Tanoue S, Uematsu H, Iemoto Y. Thermal and Mechanical Properties of Polypropylene/Boron Nitride Composites. Energy Procedia. 2013;34:808-17. [27] Selvakumar V, Manoharan N. Thermal Properties of Polypropylene/Montmorillonite Nanocomposites2014. [28] Rimdusit S, Smittakorn W, Jittarom S, Tiptipakorn S. Highly Filled Polypropylene Rubber Wood Flour Composites. 2011. 2011;15(2):14. [29] Bakar M, Ishak Z, Taib R, Rozman H, Jani SM. Flammability and mechanical properties of wood flour-filled polypropylene composites. Journal of Applied Polymer Science. 2010;116(5):2714-22.

ACCEPTED MANUSCRIPT

AC C

EP

TE D

M AN U

SC

RI PT

[30] Akar T, Tosun I, Kaynak Z, Ozkara E, Yeni O, Sahin EN, et al. An attractive agro-industrial byproduct in environmental cleanup: Dye biosorption potential of untreated olive pomace. Journal of Hazardous Materials. 2009;166(2–3):1217-25.

FIGURE CAPTIONS

Figure 1. Particle size distribution of OP powder. Figure 2. Tensile strength and Young's modulus of PP and OP filled PP composites. Figure 3. Flexural strength and flexural modulus of PP and OP filled PP composites. Figure 4. Storage and Loss modulus values of PP and OP filled PP composites. Figure 5. DSC curves of PP and OP filled PP composites. Figure 6. TG curves of PP and OP filled PP composites.

ACCEPTED MANUSCRIPT

AC C

EP

TE D

M AN U

SC

RI PT

Figure 7. XRD pattern of OP residue powder. Figure 8. XRD patterns of PP and OP filled PP composites. Figure 9. FTIR spectrums of P, PP and OP filled PP composites. Figure 10. SEM images of the composites.a) PP-10OP, b) PP-20OP,c) PP-30OP, d) PP-40OP

TABLE CAPTIONS

Table 1. Storage modulus values of OP filled PP composites at various temperature. Table 2. DSC data of PP and OP filled PP composites. Table 3. TGA data for PP and OP filled PP composites.

ACCEPTED MANUSCRIPT Table 1. Storage modulus values of OP filled PP composites at various temperature. 30°C

50°C

75°C

100°C

130°C

PP

1682.06

1384.82

844.69

540.50

303.38

PP-10OP

1860.77

1562.64

1003.83

653.10

379.07

PP-20OP

1940.75

1604.92

1005.62

645.42

366.39

PP-30OP

2168.94

1845.06

1203.46

787.43

455.98

PP-40OP

2601.73

2250.86

1501.62

997.04

581.86

Table 2. DSC data of PP and OP filled PP composites.

PP

116

167

PP-10OP

119

165

PP-20OP

118

166

PP-30OP

118

166

PP-40OP

118

∆Hc(J/g)

164

∆Hm(J/g)

M AN U

Tm (°C)

∆T(°C)

Xc (%)

94.8

74.1

51

35

90.6

76.8

46

41

82.9

72.1

48

43

70.5

57.2

48

39

51.3

46

41

TE D

Tc(°C)

Sample

SC

RI PT

Storage Modulus

57.8

EP

Table 3. TGA data for PP and OP filled PP composites. Td(°C)* at 5 % mass loss 382

Ti (°C)* 420

Tm(°C)* 453

Mass loss (600°C) % 99.8

PP-10OP

381

432

460

95.6

PP-20OP

306

445

464

80.2

PP-30OP

308

440

461

68.2

PP-40OP

282

439

463

58.3

AC C

Sample PP

*Td: Decomposition temperature, Ti: Initial decomposition temperature, Tm: Maximum decomposition temperature.

AC C

EP

TE D

M AN U

SC

RI PT

ACCEPTED MANUSCRIPT

AC C

EP

TE D

M AN U

SC

RI PT

ACCEPTED MANUSCRIPT

AC C

EP

TE D

M AN U

SC

RI PT

ACCEPTED MANUSCRIPT

AC C

EP

TE D

M AN U

SC

RI PT

ACCEPTED MANUSCRIPT

AC C

EP

TE D

M AN U

SC

RI PT

ACCEPTED MANUSCRIPT

AC C

EP

TE D

M AN U

SC

RI PT

ACCEPTED MANUSCRIPT

AC C

EP

TE D

M AN U

SC

RI PT

ACCEPTED MANUSCRIPT

AC C

EP

TE D

M AN U

SC

RI PT

ACCEPTED MANUSCRIPT

AC C

EP

TE D

M AN U

SC

RI PT

ACCEPTED MANUSCRIPT

AC C

EP

TE D

M AN U

SC

RI PT

ACCEPTED MANUSCRIPT