Mechanical and Rheological Behavior of Basalt and Hemp Fiber Reinforced Thermoplastic Composites
Automotive Composites Conference & Exhibition (ACCE) Novi, Michigan September 4-6,2019
Mechanical and Rheological behavior of basalt and hemp fiber reinforced thermoplastic composites
Bharath K. Nagaraja, Vikram Yadama, and Lloyd V. Smith Composite Material and Engineering Center Washington State University, Pullman, WA
Composite Materials and Engineering Center Introduction
• Natural fibers offer several advantages, such as being renewable materials and weight, for use in bio-products and bio-composites • However, they have an affinity for water, are more susceptible to fire, have greater variation, and interact poorly • This study proposes potential solutions to overcome some of these shortcomings to produce bio-based composites for automotive applications • Automotive industry is actively exploring synthetic materials, such as glass fiber and carbon fiber reinforced composites, but there is also a desire to use more materials that are renewable and can be recycled
2 Composite Materials and Engineering Center Long-term goal of the project
• To investigate the influence of Natural fiber (Hemp Fiber) on Basalt fiber/PP/MAPP composites • Using mixture model design to obtain different formulations • To evaluate tensile strength, stiffness, toughness, flexural, impact, dimension stability and to study the morphology • Also, study the fire and sound properties of these composites
3 Composite Materials and Engineering Center Objectives of this talk
The objective of the work are to: ➢ Investigate the influence of formulation on the performance of injection molded basalt fiber/PP composite material ➢ Investigate the effect of MAPP on the basalt fiber/PP composites ➢ Evaluate the influence of fiber content on fiber/thermoplastic resin for tensile strength and modulus ➢ Study the rheological behavior of hybrid basalt/hemp fiber reinforced polypropylene composites
4 Composite Materials and Engineering Center Chemical composition and properties of Basalt fiber and Hemp fiber
ChemicalMajor Chemical Composition of Basalt Major Chemical Percentages Percentages Composition of Basalt Fiber Composition of Hemp Fiber
SiO2 51.6-59.3 Cellulose 77.5
Al2O3 14.6-18.3 Hemi-cellulose 10 CaO 5.9-9.4 Lignin 6.8 MgO 3.0-5.3 Pectin 2.9 ✓ Service temperature range -452° F to Fat and Wax 0.9 1,200° F (-269° C to +650° C) ✓ Density – 0.8 gm/cc ✓ Density - 2.6 gm/cc ✓ Cost-effective ✓ Excellent shock resistance - good for ✓ Reduces molding time ballistic applications ✓ Weight reduction in finished part ✓ Higher oxidation & radiation resistance ✓ Can be customized to meet a variety ✓ Good fatigue and corrosion resistance of specifications and different manufacturing systems ✓ Better chemical resistance than E-glass
Source: Compressive Stress-Strain Behavior of HSFRC Reinforced with Basalt Fibers, Journal of Materials in Civil Engineering 2015, 28(4) 5 Composite Materials and Engineering Center Thermoplastic resins Properties
Polypropylene from RheTech
➢ Density: 0.8965 g/cm3
➢ Tensile Strength at yield, MPa: 22.6
➢ Notched charpy at 23°C: 11 KJ/m2
➢ Melting Point: 162°C (324°F)
➢ Heat deflection temperature at 0.45 Mpa: 118 °C
➢ Melt flow rate, 230 °C/2160 g: 26 dg/min (avg)
Sources: Material specification data, RheTech 6 Composite Materials and Engineering Center Mixture design for composites
Table: Design of Experiments
Basalt Fiber : 0 < X1 < 35 Component 1 Component 2 Component 3 MAPP : 0 < X2 < 5 Run A:Basalt B:MAPP C:PP Polypropylene : 65 < X3 < 100 % % % 1 0 5 95 2 8.125 3.75 88.125 3 23.125 3.75 73.125 4 0 0 100 5 15 5 80 6 35 0 65 7 0 5 95 8 17.5 0 82.5 9 21.6667 1.66667 76.6667 10 35 0 65 11 30 5 65 12 17.5 0 82.5 Condition : X1 + X2 + X3 = 100 13 30 5 65 14 16.25 2.5 81.25 15 11.6667 1.66667 86.6667 16 0 2.5 97.5 17 0 0 100
7 Composite Materials and Engineering Center Images of equipment's and blended granules
Extruder ✓ Screw Speed: 40 rpm ✓ Chamber temp: 180 deg C (9 Chambers)
To avoid Porosity in samples ✓ Extruded samples were dried at 120 deg Celsius for 2 hrs ✓ Injection pressure increased from 600 -700 bars ✓ Chamber temperatures: 180-180-180-180 deg C ✓ Mold temperature in injection molding increased from 60 to 100 deg Celsius 8 Composite Materials and Engineering Center Tensile test specimens
ASTM D 638 Standard is followed to - maintain the dimensions of the sample - test procedure like speed - evaluate tensile strength and tensile modulus
9 Composite Materials and Engineering Center Results of Tensile Test for Basalt/PP/MAPP specimens
• Addition of MAPP in composites indicates high ultimate tensile strength and Young’s modulus upto 3.75 wt%, further decreases with increase in MAPP • Up to 28 % increase in UTS and 17 percent of increase in Young’s modulus was observed
10 Composite Materials and Engineering Center ANOVA and Two component mix results for UTS
Response 1: UTS Sum of Mean Source df F-value p-value Squares Square 7.968E+0 Model 4.781E+06 6 6.59 0.0049 significant 5 ⁽¹⁾Linear 1.292E+0 2.583E+06 2 10.69 0.0033 Mixture 6 AB 10805.59 1 10805.59 0.0894 0.7710 AC 1471.54 1 1471.54 0.0122 0.9143 BC 3.99 1 3.99 0.0000 0.9955 1.721E+0 ABC 1.721E+05 1 1.42 0.2602 5 1.208E+0 Residual 1.208E+06 10 5 2.201E+0 Lack of Fit 1.100E+06 5 10.18 0.0118 significant 5 Pure Error 1.081E+05 5 21625.40 Cor Total 5.989E+06 16
P-values indicate basalt fiber and polypropylene are significant terms.
11 Composite Materials and Engineering Center Contour and 3D surface plot for UTS
➢ Significant improvement in BF-PP interaction with addition of MAPP ➢ With increase in MAPP – an increase of 28 % in UTS at 30% Basalt fiber
12 Composite Materials and Engineering Center ANOVA and Two component mix results for tensile modulus Response 2: E
Sum of Mean Source df F-value p-value Squares Square Model 7.222E+10 6 1.204E+10 5.45 0.0096 significant
⁽¹⁾Linear 5.629E+10 2 2.815E+10 12.75 0.0018 Mixture
AB 1.376E+09 1 1.376E+09 0.6230 0.4482
AC 1.172E+10 1 1.172E+10 5.31 0.0440
BC 1.634E+09 1 1.634E+09 0.7397 0.4099
ABC 5.694E+08 1 5.694E+08 0.2578 0.6226
Residual 2.208E+10 10 2.208E+09 not Lack of Fit 1.533E+10 5 3.066E+09 2.27 0.1946 significant Pure Error 6.754E+09 5 1.351E+09
Cor Total 9.431E+10 16
P-values indicate basalt fiber and polypropylene are significant terms.
13 Composite Materials and Engineering Center Contour and 3D surface plot for tensile modulus
➢ Significant improvement in BF-PP interaction with addition of MAPP ➢ With increase in MAPP – an increase of 17 % in Young’s modulus at 30% Basalt fiber 14 Composite Materials and Engineering Center Rheological Behavior
• Rheological behavior is studied to know the flow of material under the circumstances in which they respond with plastic flow instead of deforming elastically due to the applied force • The oscillatory experiments render the information on both elastic and viscous properties of the formulations and hence provide more detailed characterization of dispersion and interface • This study sought to develop the methodology to produce basalt fiber/hemp fiber reinforced in thermoplastic resin • To evaluate complex viscosity(η), storage modulus (G`), loss modulus (G``) and damping factor (Tan δ ) of these composites
15 Composite Materials and Engineering Center Materials used
Materials - ✓ Basalt fiber/Hemp fiber ✓ MAPP ✓ Polypropylene
Formulation – Sample Name Basalt Fiber Hemp Fiber MAPP Polypro- pylene 15B15H70PP 15 15 00 70 15B15H5MA65PP 15 15 05 65 30B5MA65PP 30 00 05 65 30H5MA65PP 00 30 05 65
16 Composite Materials and Engineering Center Experimentation
• The rheological behavior of Basalt fiber/hemp fiber reinforced thermoplastic composite was investigated at constant temperature over a wide range of frequencies • The effect of hemp fiber and coupling agent on melt rheological properties were investigated • The tests were performed in the dynamic mode and 25- mm parallel plate geometry with gap setting of about 2 mm • The temperature was 200 deg C and the frequency, varied between 0.1 and 200 rad/s
17 Composite Materials and Engineering Center Results
✓ Viscosity increases with increasing Hemp fiber content
✓ Composite without MAPP showed the lowest viscosity compared to other samples in whole range of frequency
✓ Since the complex viscosity represents the viscoelastic resistance of the polymer melt during flow, a high viscosity implies a natural fiber (hemp hurds >300 microns) – matrix interaction
✓ The greater fiber–polymer interaction means greater the resistance to flow and greater the viscosity [1,2]
18 Composite Materials and Engineering Center Results
✓ Samples containing MAPP showed higher viscosity than ones without coupling agent. This can be explained by the formation of strong network of PP–fiber in the presence of coupling agent
✓ When the storage modulus (G`) is considered, the basalt/hemp fiber composites have higher rigidity than other composites, this increase being strongly dependent on proportion, which shows good fiber- matrix adhesion existed [3] ✓ Viscous behavior becomes less pronounced with higher fiber loading in PP matrix and a inclination to a slow shift from viscoelastic liquid-like to solid-like behavior occurs
19 Composite Materials and Engineering Center Results
▪ It is evident that G`` increased linearly with the increase in frequency
▪ Hybrid composite of 15 wt% basalt fiber and 15 wt% of hemp fiber with 5 wt% MAPP and 65 wt% of PP shows better viscous properties over other composites ▪ With increasing of hemp fiber, enhanced discontinuity may effect in the squeezing out the polymer to the surface of the composites which is necessary to create continuity on the surface [4]
▪ 30 wt% hemp fiber content, will affect the continuity due to the presence of fiber in bulk of melt which results in decrease of viscous behavior (loss modulus)
20 Composite Materials and Engineering Center Results
❑ The ratio G’’/G’ decreases with increase of hemp fiber content ❑ Tan δ shows to decrease with the increase of the hemp fiber which indicates the elastic component is more affected by hemp fiber loading than viscous material ❑ Loss of energy by the hemp fiber is less than storage modulus due to stronger mechanical lock up by fiber– polymer interaction [5] ❑ with incorporation of fiber into polymer G' increased and G" decreased due to the reduction of energy loss by porous material, hence tan δ decreased. The flat section in the curve point out the relaxation of the fibers in composites [6]
21 Composite Materials and Engineering Center Conclusions
• Increase in MAPP and basalt fiber will increase the mechanical properties of the composites. • The steady state viscosity of the composites increased with the incorporation of fibers • The composites with MAPP showed enhanced viscosity values due to improved fiber matrix adhesion (backs up the result of DoE) • The complex viscosities were quite high at the low frequency but decreased with increasing frequency indicating a shear thinning behavior of the fiber composites • The G` and G``of the all the composites increased with increasing ω except for 30 wt% hemp fiber which exhibited decrease in storage modulus with increasing frequency • The damping factor decreased with increasing frequency for all composites 22 Composite Materials and Engineering Center References
1. Smita Mohanty And Sanjay K. Nayak, Polymer Engineering And Science, 47 (10), 2007, 1634-1642. 2. Eddy Twite-kabamba, Ahmed Mechraoui And Denis Rodrigue, Polymer Composites, 30 (10), 2009, 1401-1407. 3. T.Q. Li, M.P. Wolcott, Polymer Engineering And Science, 46 (4), 2006, 464-473. 4. 0. S. Carneiro And J. M. Maia, Polymer Composites, 21 (6) 2000, 960-969. 5. H. Azizi and I. Ghasemi, Polymer Composites, 30 (4), 2009, 429-435. 6. Anselm O. Ogah, Joseph N. Afiukwa and A. A. Nduji, Open Journal of Polymer Chemistry, 4, 2014, 12-19.
23 Composite Materials and Engineering Center Acknowledgments
NSF I/UCRC Grants (#1439732, #1738669) Center for Bioplastics and Biocomposites (CB2) Project Mentors (from CB2 Industry Advisory Board) Drew Geda, Hyundai Tina Tosukhowong, GC Innovation Jim Preston, RheTech Nate Tortorella, John Deere Alper Kiziltas, Ford
24 Composite Materials and Engineering Center Thank you Questions ?
25 Composite Materials and Engineering Center