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Vol. 9, Issue 1; January - February 2024; 

ISSN: 2837-2964 

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13 | A c a d e m i c  J o u r n a l  o f  S c i e n c e ,  E n g i n e e r i n g  a n d  T e c h n o l o g y  

|  https://topjournals.org/index.php/AJSET 

 

STRUCTURAL CHARACTERISTICS OF HIGH-DENSITY POLYETHYLENE 
MATRIX COMPOSITES ENHANCED BY OPEN-AIR AND FURNACE RICE HUSK 
ASH 
 
1Dennis O. Omambia., 1Peter K. Kamweru, 2John M. Gichumbi, and 2Faith G. Ndiritu 
1Department of Physical Sciences, Faculty of Science, Engineering and Technology Chuka University, 
Kenya. 
2Department of Physics, Faculty of Science, Egerton University Egerton University, Kenya.  
DOI: https://doi.org/10.5281/zenodo.10592549 
  

Abstract: In this work, rice husks ash (RHA) was introduced to pure and recycled high density polyethylene 
(HDPE) matrix, at varying ration (0-50%) to formulate rice husks ash High density polyethylene (RHAHDPE) 

composite. RHA was obtained by burning fresh rice husks either by open-air burning (oRHA) or furnace 
calcination at 700°C  (fRHA). The composite samples were made by melt-mixing the HDPE in an oven at a 

temperature of 150°C and adding different percentages of RHA in presence of maleic anhydride 

compatibilizer. Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM) 
were carried out to determine the structural properties of the samples, and both suggest occurrence of 

composting chemical changes. For all RHA-HDPE samples, a broad band was noted between 970-070cm-1. 
This was highly contributed by the RHA and associated to Si-O-Si stretching modes. Other peaks are 

associated with Si-O-C interaction and O-Si-O bending vibrations in the samples. Scanning electron 
Microscopy (SEM) micrographs for HDPE indicated a smooth and uniform surface with a number of voids. 

On addition of RHA, the particles filled these voids making the sample surface rough. This roughness is seen 
to increase with increased percentage of RHA. The studies conclude that the cheaply obtained oRHA is as 

good as the fRHA in making RHA-HDPE composite.  
Keywords: RHA-HDPE composites, maleic anhydride compatibilizer, rice husks, rice husks ash, Fourier 
Transform Infrared Spectroscopy (FTIR, scanning electron microscopy (SEM). 
 

INTRODUCTION  
High-density polyethylene (HDPE) is a thermoplastic 1995; Zhang et al., 2004), it has found diverse polymer 
produced from the monomer ethylene, and one applications that include household appliances, of the most 
important commercial polyolefin. Due to its automobiles, wiring and cables, aeronautics and excellent 
combination of properties (Diraddo and Laroche, packaging.  However,  HDPE  and   its   wide   use   have 
drawbacks that emanates from its poor weatherbility (Khan and Ahmed, 2003; Zebarjad et al., 2006). To improve 

HDPE properties and reduce cost, fillers such as natural fibers (Lei et al., 2007), sisal fibers (Li et al., 2008), 

Kenaf fibers (Salleh et al., 2014) back fibers (Yemele et al., 2010) can be blended with HDPE amongst others as 

in the reviewed in various literature (Sarasini and Fiore, 2018; Dashtizadeh et al., 2017; Ng et al., 2020). Rice 

husks (RH), are a byproduct of rice milling process and produced in large quantities. For instance, the world rice 

production was approximately 782 million tonnes in 2018 (FAO, 2020). Rice husks constitute 20 % of rice paddy, 

and its composition is as follows: cellulose (50%), lignin (25–30%), silica (15– 20%), and moisture (10–15%). 

Bulk density of rice husk is low and lies in the range 90–150 kg/m3 (Singh, 2018). These proportions may however 

change depending on the geographical conditions, rice variety, methods of sample preparation and analysis among 

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 Academic Journal of Science, Engineering and Technology 
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ISSN: 2837-2964 

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14 | A c a d e m i c  J o u r n a l  o f  S c i e n c e ,  E n g i n e e r i n g  a n d  T e c h n o l o g y  

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others (Chandrasekhar et al., 2003; Johar et al., 2012). Rice husk has low commercial value, and when burnt to 

extract energy, the ash is of low value and most of it ends up in landfills (Govindarao, 1980; Shivam et al., 2019). 

This among other reasons has attracted research interests to use ash obtained from burning rice husks as fillers in 

thermoplastic polymers (Zaaba and Ismail, 2019). The use of RHA as a filler in HDPE offers a twopronged 

advantage, that is, it reduces pollution of both waste rice husks and HDPE (Kohl et al., 2020; Van Thanh et al., 

2020), and it ultimately leads to production of a novel material with its properties enhanced (Abdul Azam et al., 

2020; Collazo-Bigliard et al., 2019). This was the motivation of this study.  
Formulation of RHA-HDPE composites and their characterization has been undertaken in some studies in 
different ways. For instance, in their study on rice husk ash as a valuable reinforcement for high density 
polyethylene, Ayswarya et al. (2012) were able to formulate RHA-HDPE composites of different percentages. 
Compatibilization was first done where the compatibilizer (MA-g-HDPE) was a grafting reaction between maleic 
anhydride (MA) and HDPE with the help of dicumyl peroxide (DCP) initiator at 145 . The study amongst others 
like, Ginting et al. (2017) and Daramola et al. (2015), did not consider higher percentages of RHA neither did 
they consider the properties of the composites made by RHA from uncontrolled burning of rice husks which is a 
cheaper way of obtaining RHA.   
Another study conducted by Dominic et al. (2014) on rice husk silica as an efficient biofiller in high density 
polyethylene, pretreatment of rice husks with HCl was first done followed by calcination in a furnace at 650  for 
6h to get silica. HDPE was then allowed to melt at 145 for two minutes and then varying amounts of RHS (0.5-
3 wt%) were added and mixed to form the composite. The test specimens were then cut from the cooled blends. 
SEM micrographs of pure  HDPE  showed  a number of voids. On addition of RHS, the RHS particles  occupied 
the voids uniformly providing more reinforcement. The wavy texture of HDPE-RHS surface showed signs of 
greater energy absorption. FTIR analysis of the samples was not conducted as well as considering RHA instead 
of RHS. Ginting et al. (2014) in his study on preparation and characterization of RHA as a filler material into 
nanoparticles of HDPE thermoplastic composites, the composites were made by mixing HDPE, nanoparticle 
RHA and PE-g-MA in different percentages of HDPE (100, 95, 93, 91, 89, 87 wt %). A constant amount of 
compatibilizer (3% wt) was used. A different study was done by Tong et al. (2014) on mechanical and 
morphological properties of recycled HDPE composite using rice husk filler. The RH fibers were first dried in an 
oven to reduce the moisture content. The compounding of the fibers and recycled HDPE with the coupling agent 
(MA-g-HDPE) was done. Five different fiber loadings (0, 10, 20, 30 and 40% wt) were used. For structural 
characterization of the samples, SEM micrograph image for 0% wt RH fiber showed no clear gaps in between the 
recycled HDPE particles. This proved that recycled HDPE was well mixed during the extrusion process. For 20% 
wt RH fibers, SEM image showed no clear gaps between RH fibers and recycled HDPE matrix indicating good 
interface bonding. For 40% wt RH fiber, the fibers were perfectly attached to the matrix and were evident that 
the fibers were strongly imbedded in the matrix. FTIR analysis was not carried out. Also, RHA was not considered 
in preparation of the samples.  
Parvinzadeh et al. (2010) studied on Surface Characterization of Polyethylene terephthalate/Silica 
nanocomposites. In their study, an ATR-FTIR was done on the samples. It was found that there was a broad band 
at 3200-3400 cm-1, intense bands at 3000-3200 cm-1 and bands at 1600-1800 cm-1. These bands were related to 
intermolecular O-H bonds, CH2 asymmetric stretching and C=C or C=O stretching vibrations. The –OH 
stretching vibrational peak became broader at 3200-3400 cm-1 band due to hydrogen bonds. This was for the 
hydrophilic nanosilica incorporated into PET matrix. Other sharp bands at 1400-1600 cm-1 and 950-1250 cm-1 
were assigned to C=C stretching and C-H in plane bending of benzene rings. It was also noted that on addition of 

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 Academic Journal of Science, Engineering and Technology 
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ISSN: 2837-2964 

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15 | A c a d e m i c  J o u r n a l  o f  S c i e n c e ,  E n g i n e e r i n g  a n d  T e c h n o l o g y  

|  https://topjournals.org/index.php/AJSET 

 

hydrophilic nanosilica into the PET matrix, the O-H intermolecular bonds and CH2 stretching vibrations were 
intensified. A more intense band was also noted at 10001200 cm-1 related to Si-O-C interactions in the 
PET/hydrophilic nano-silica composites. SEM micrographs indicated that the PET had a smooth and uniform 
surface. On adding nano-silica particles to the matrix, nano-silica particle-particle and nano-silica particle-PET 
chain interactions led to formation of agglomerates on the surface of PET composites. This led to increased 
surface roughness of the composites. HDPE and RHA were not incorporated in this study.   
The aim of this study was to composite RHA and HDPE   
the injection hole. 
(both from pellets and packaging containers). In this study however, it is sought to obtain rice husks in two ways, 
that is, through open air burning, which is cheap but mostly results to RHA with amorphous silica, and secondly, 
through controlled furnace calcination that would prove expensive but results to crystalline silica in the ash when 
right temperature conditions are chosen. The author sought to compare the properties of the composites made 
from HDPE that is recycled from old used packaging containers, and pure HDPE pellets obtained from plastic 
industries in Nairobi, Kenya using Fourier transform infrared spectroscopy (FTIR) and scanning electron 
microscopy (SEM)     

MATERIALS AND METHODS   

Materials   
HDPE was obtained in two ways; first as HDPE pellets from industries and also in form of HDPE packaging 
containers collected from Chuka municipality dumpsites in Tharaka Nithi County, Kenya. Pure HDPE has a melt 
flow index of 16 g/10 min (190 /2.16 kg) and a melting temperature range of 130-160  (Dominic et al., 2014). 
Other chemicals used were maleic anhydride and hydrogen peroxide obtained from sigma aldrich. RHA was 
obtained open air burning (oRHA) and furnace (fRHA) calcination at 700 .  
  

RHA (% )   HDPE (%)   

0   

5   

10   

100   

95   

90   

25   

35   

75   

65   

50   50   

 

 

 
 

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 Academic Journal of Science, Engineering and Technology 
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16 | A c a d e m i c  J o u r n a l  o f  S c i e n c e ,  E n g i n e e r i n g  a n d  T e c h n o l o g y  

|  https://topjournals.org/index.php/AJSET 

 

Methodology  

Compatibilization  
The compatibilizer (MA-g-HDPE) was made by  melt  mixing  HDPE and maleic anhydride (MA) in the ratio 
90:10 with the help of hydrogen peroxide (H2O2) initiator (6% wt) in the molten state. It was allowed to solidify 
and then used in the preparation of RHAHDPE blends. This followed a modified procedure as done by Ayswarya 
et al. (2012) and Montanheiro et al. (2016).   

Preparation of the HDPE-RHA Composite   
Samples collected from the dumpsite were heavily washed and allowed to dry to avoid contamination of the 
samples; it was cut into small pieces then melted as follows. HDPE was allowed to melt in an oven at a temperature 
of 150  for 20 min then varying amounts of RHA were added as indicated in Table 1 and a constant amount of 
compatibilizer (consisting of 15 % of the weight of the total blend) was blended with HDPE. The mixture was 
mechanically stirred to ensure a homogenous mixture. Exact masses of RHA and HDPE were measured using an 
analytical balance. The molten mixture was then allowed to cool to room temperature after being injected into the 
designed metallic mold chamber, whose design and dimensions are shown in Figure 1. The injection was made 
easier using a designed metallic syringe designed as shown in Figure 2. After cooling, it was then cut into samples 
to be used for the different characterizations. 

Structural characterization  
This was determined following the method of Mohamad (2007) using Fourier Transform Infrared Radiation 
(FTIR). The FTIR spectra for the samples were recorded on an ATR Perkin Elmer A100 spectrometer. The 
resolution was 4 cm-1 and each sample was scanned four times at a range of 4000-380  cm -1. Morphology and 
particle size determination followed a modified procedure obtained from Ghasemi  and Younesi (2011), using 
Zeiss Ultra plus   

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17 | A c a d e m i c  J o u r n a l  o f  S c i e n c e ,  E n g i n e e r i n g  a n d  T e c h n o l o g y  

|  https://topjournals.org/index.php/AJSET 

 

  

  
Figure 2. Plunger for injecting molten HDPE-MA-RHA mixture.  

  

  

 

 

Figure 3. FTIR Spectra of pure HDPE pellets.  

  

  

  
Scanning Electron Microscopy (SEM) operated at 5 kV. The prepared samples were first sprinkled uniformly 
over an adhesive tape and spatter coated with a thin layer of gold, and an electron acceleration voltage of 20 kV 
was applied.   

RESULTS AND DISCUSSION   
FTIR Spectra of pure HDPE and recycled HDPE   
The FTIR spectra of pure HDPE and recycled  HDPE  are  shown in Figures 3 and 4, done for wavenumbers 
between 4000 cm-1 and 380 cm-1. The peaks for pure and recycled HDPE were similar. There are two similar 
prominent sharp peaks for the two types of HDPE between 2914 cm-1 and 2849 cm-1 showing that they have the 
highest transmittance of IR at this region. The other peaks are also in close range to each other as seen in the 
spectra for both types of HDPE (Lin et al., 2015). During manufacture of plastic products there are many additives 
added,  mostly dependent on the polyolefin type   
Figure 5. FTIR Spectra of oRHA and fRHA. and end use of the product. Luckily as outlined in a study by 

Hahladakis et al. (2018), stabilizers, antioxidants and UV stabilizers additives are used in lower quantities or none 

in polyethylene products (HDPE and LDPE). It gives assurance that the HDPE obtained from recycling doesn’t 

differ much from pure HDPE. This was similar results to the study by Hadi et al., 2014. It is now expected, similar 

to a study by Adhikary et al. (2008), that the properties of the composites based on recycled HDPE will be 

equivalent to those based on pure HDPE.   

FTIR spectra of open air burnt and furnace calcined  

RHA  
FTIR  spectra  of  oRHA and fRHA are shown in Figure 5.  
35 % fRHA.  
The broad band evident in oRHA peaking at 3398.87 cm-1 represents the silinol OH groups and surface adsorbed 
water (Ren et al., 2013; Zhang et al., 2013), and it is absent in fRHA. This was shown in other studies (Deshmukh 
et al., 2012). Another unique and differentiating band in oRHA is the band peaking at 1603.15, representing C=C  

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18 | A c a d e m i c  J o u r n a l  o f  S c i e n c e ,  E n g i n e e r i n g  a n d  T e c h n o l o g y  

|  https://topjournals.org/index.php/AJSET 

 

 

 
Stretching of aromatic carbon (Chuai et al., 2001; Khalil et al., 2001; Prachayawarakorn and Yaembunying, 
2005). The peaks between 1200 cm-1 and 700 cm-1 represents the vibration modes of the Si-OSi network (Della 
et al., 2002). The peaks at 1051.24 cm-1 for fRHA and 1052.95 cm-1 for oRHA show the silixone groups Si-O-Si 
(Pongdong et al., 2015). The band at 443.24 cm-1 and shifted to 447.53 cm-1   is associated to Si-O bending mode 
(Della et al., 2002). These peaks show the presence of SiO2 with a slight peak shifting that matches earlier studies. 
This   indicates the presence of Nano structured SiO2 in the RHA, as expected.   
 Figure 4. FTIR Spectra of recycled HDPE. 

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19 | A c a d e m i c  J o u r n a l  o f  S c i e n c e ,  E n g i n e e r i n g  a n d  T e c h n o l o g y  

|  https://topjournals.org/index.php/AJSET 

 

  
FTIR spectra of the RHA-MA-HDPE composites   
Figure 6 to 9 shows the spectra of RHA and compatibilized   HDPE-RHA    composites    for   different proportions 
of RHA and the two different RHA preparation methods. The FTIR spectra broadly shows peaks around the 
following larger bands, 995.08-1068.37 , ,   
 1324.86-1473.35  2048.03-2074.07, 2821.35-2914.88 and 3659-3698.80 cm-1. There is a great similarity in the 
peaks was noted for samples with 5, 10 and 35% fRHA.  Additional peaks exist at 875-450 cm-1   for the RHA-
MAHDPE made composited of 50% oRHA is evident. These are the peaks present in the RHA before 
compositing. This could mean that most of the RHA at this percentage mix ratio has not blended well in the 
HDPE matrix. It could have agglomerated into pockets within the HDPE without forming a uniform blend. 
However, other peaks have slightly shifted for the RHA-HDPE samples compared to those of pure ash and pure 
HDPE indicate changes in structure. This is due to formation of new bonds between the –OH and Si-O-Si groups 
in the RHA and –CH group in the HDPE.  
The peaks between, 3655.41-3708.44 cm-1 in the sample with 5, 10 and 35% RHA (both oRHA and fRHA), show 
the presence of O-H group in the RHA arising from silanol functional groups. There is a broad band at 3599.19 
cm-1 for 25% fRHA-recycled HDPE, 3567.78 cm- 1 -1  for  25%  open-air RHA-pure  HDPE,  3482.80  cm  for 
35 % oRHA.  
50% fRHA-recycled HDPE, 3436.34 cm-1 for 50% openair RHA-recycled HDPE and 3418.08 cm-1 for 50% 
openair RHA-pure HDPE. These bands are related to intermolecular O-H bonds. The sharp peaks at 2848.03 cm-

1 and 2914.99 cm-1(100% recycled HDPE) which shift slightly to 2848.08 and 2914.92 cm-1 (100% pure HDPE) 
appear as one broad band between 2808.81-2914.88 cm1 . This is for all 5, 10 and 35% RHA except for the 35% 
open-air RHA-pure HDPE where it appears between 2872.45-2986.23 cm-1. These intense broad peaks are 
associated with CH2 asymmetric stretching. The broad peak is also associated with –OH group and chemically 
absorbed water in the RHA. The prominent peak at 2074.07 cm-1 which shifts to 2073.10, 2034.59, 2019.92 and 
2028.35 cm-1 (5, 10 and 35% RHA spectra) is related to C=C or C=O stretching vibrations. Other smaller peaks 

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20 | A c a d e m i c  J o u r n a l  o f  S c i e n c e ,  E n g i n e e r i n g  a n d  T e c h n o l o g y  

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were noted between 1500-1800 cm-1 for 25% fRHA-pure and recycled HDPE, 50% fRHA-recycled HDPE, 50% 
oRHA-recycled HDPE and 50% oRHA-pure HDPE.  
These were also associated with C=C or C=O stretching vibrations. Between, 1400-1500 cm-1 there appeared 
sharp peaks which were much longer for 0,  25  and  50% RHA. A broad band with slightly sharp peaks at the 
end appeared between, 1300-1350 cm-1. These are associated with C-H in plane bending. The broad band between 
970-1090 cm-1 for all RHA-HDPE samples is associated with Si-O-Si stretching modes. Other smaller sharp 
peaks appeared between 750-910 cm-1 and much sharper and longer peaks between 700-730 cm-1 for the 25% 
and 50% RHA samples. These are related to Si-O-C interactions in the RHA-HDPE blends. For these samples, a 
broad peak is also noted between, 440-470 cm-1.  It is highly contributed by the RHA and is associated with O-
Si-O bending vibration in the ash samples.   

SEM analysis   
Figure 10 shows the SEM micrographs of HDPE both pure and recycled at a higher magnification of 20 kx. There 
is evidence of ‘smooth’ homogeneous matrix in both, but with voids that could easily be filled by filler materials. 
Figure 11  shows  SEM  micrographs  for  25%   
35 % fRHA. 
RHA-HDPE samples for various magnifications.  There is evidence of agglomeration of RHA on the surface of 
HDPE composites. Lower magnification spectra for these samples show distinction between RHA particles and 
HDPE particles. RHA particles of irregular shapes and non-uniform distribution are also observed. Voids are also 
seen on the surface indicating its roughness. The surfaces also tend to appear smooth as the magnification 
increases. There is a homogenous dispersion of RHA particles in the matrix showing uniform composition of 
RHA-MA-g-HDPE. Due to its low percentage in these composites, RHA could not fill all the voids in the HDPE. 
Also, at this magnification there appear no clear gaps between the RHA and HDPE matrix indicating good 
interface bonding.  
Figure 12 shows micrographs for 50% RHA-HDPE composites (magnification 20000×). The micrograph shows 
thermal eradication of the organic matter in the rice husk ash by forming residual pores within the ash sample. 
This is an ultimate indicator of porous active silica with large  internal surface  area.  The  color  of  the silica is 
grey, with loose flakes showing plate-like morphology (Farooque et al., 2009).  

Conclusion  
FTIR analysis for the RHA-HDPE samples showed that there were structural changes due to addition of RHA 
into the HDPE. It was also observed that the sharp peaks in the HDPE converted to broad peaks in these samples. 
All the 5% RHA- HDPE blends had a common transmittance at 2074.07 cm-1 which shifted to 2073.10 cm-1 for 
the 10% fRHA-pure HDPE. The 25% RHA-HDPE spectra were similar to those of HDPE with very slight shifts 
in peaks. For the 50% RHA-HDPE blends, the spectra appeared as a combination of both the RHA spectra and 
HDPE spectra. This meant that they contributed equally to the structure formation. In terms of functional groups, 
sharp peaks appeared between 3655.41-3708.44 cm-1 for the 5, 10 and 35% RHA samples showing the presence 
of O-H group in the RHA arising from silanol molecules. Broad bands  are  seen  to appear in some of the 25% 
RHA and   

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Figure 9.  FTRI spectra for oRHA-MA-HDPE (recycled) composites (i) 5 % oRHA (ii) 10% oRHA 
and (ii) 35 % oRHA. 

    

   
  
Figure 10. SEM micrographs for HDPE for a. Pure b. Recycled.  
50% RHA blends. These are related to intermolecular O- are associated to CH2 asymmetric stretching, -OH group 
H bonds. Some of the sharp peaks in HDPE appear as a and chemically absorbed water in the ash.  broad band in 
the 5, 10 and  35%  RHA  samples.  These Sharp  peaks  between, 1400-1500 cm-1 were observed  

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Figure 11. SEM micrographs for 25% RHA-MA-g-HDPE a. magnification at 25 X b. 
magnification at100 X c. magnification at 1 kX d. magnification at 5 kX e. magnification at 10 
kX  f. magnification  at 20 kX.  

  

  

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Figure 12. SEM micrographs for 50% RHA-HDPE samples (magnification 20000×) for oRHA with a. pure 
HDPE, b. recycled HDPE and for fRHA c. Pure HDPE and d. recycled HDPE. for the 0, 25 and 50% RHA 
samples. These are related to C-H in plane bending of benzene rings.  SEM analysis for the RHA-HDPE samples 
indicated that the surface for the 100% HDPE initially appeared smooth and uniform with a wavy texture. On 
addition of different percentages of RHA, SEM indicated that the surface texture for the samples roughens as the 
RHA percentage increases. RHA fills the voids in the HDPE making it to appear rough. Also, different 
magnifications show different surface textures for the same sample. Therefore, production of the oRHA is cheaper 
and has almost similar or better properties as compared to industrial made which is expensive and much involving. 
The production of oRHA through this method will also help control the pollution caused by RHA ash as 
sometimes the ash lacks deposition sites ending up becoming a menace in the society. The reinforcement of the 
HDPE with the oRHA is predicted to improve the mechanical properties of the HDPE. This study recommends 
the use of more equipment in the structural analysis of the composites. Also, specific and different temperatures 
can be considered especially for the fRHA. Other percentages of RHA can also be used to make more samples 
for more detailed analysis. Further studies on the mechanical properties are encouraged.  

CONFLICT OF INTERESTS   
The authors have not declared any conflict of interests   

REFERENCES  

Abdul Azam FA, Rajendran RNR, Yuhana NY, Mohd RNA, Ahmad S, Sulong AB (2020). Fabrication of Porous 

Recycled HDPE Biocomposites Foam: Effect of Rice Husk Filler Contents and Surface Treatments on the 
Mechanical Properties. Polymers 12(2):475.  

Adhikary KB, Pang S, Staiger MP (2008). Dimensional stability and mechanical behaviour of wood–plastic 
composites based on recycled and virgin high-density polyethylene (HDPE). Composites Part B: 

Engineering 39(5):807-815.  

Ayswarya EP, Francis KV, Renju VS, Thachil ET (2012). Rice Husk Ash–A Valuable Reinforcement for High 
Density  

Polyethylene. Materials and Design 41:1-7.  

 Chandrasekhar SATHY, Satyanarayana KG, Pramada PN, Raghavan P, Gupta TN (2003). Review processing, 

properties and applications of reactive silica from rice husk—an overview. Journal of Materials Science 
38(15):3159-3168.  

Chuai C, Almdal K, Poulsen L, Plackett D (2001). Conifer fibers as reinforcing materials for polypropylene based 
composites. Journal of Applied Polymer Science 80(14):2833-2841.  

Collazo-Bigliardi S, Ortega-Toro R, Chiralt A (2019). Improving properties of thermoplastic starch films by 

incorporating active extracts and cellulose fibres isolated from rice or coffee husk. Food Packaging and 
Shelf Life 22:100383.  

mailto:topacademicjournals@gmail.com


    

 Academic Journal of Science, Engineering and Technology 
Vol. 9, Issue 1; January - February 2024; 

ISSN: 2837-2964 

Impact Factor: 6.67 

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https://topjournals.org/index.php/AJSET/index; mail: topacademicjournals@gmail.com 

 

 

 

 

24 | A c a d e m i c  J o u r n a l  o f  S c i e n c e ,  E n g i n e e r i n g  a n d  T e c h n o l o g y  

|  https://topjournals.org/index.php/AJSET 

 

Daramola OO, Oladele IO, Adewuyi BO, Sadiku R, Agwuncha SC (2015). Influence of Submicron Agro Waste 
Silica Particles and Vinyl Acetate on Mechanical Properties of High Density Polyethylene Matrix 

Composites. West Indian Journal of Engineering 38(1).  

Dashtizadeh Z, Abdan K, Jawaid M, Khan MA, Behmanesh M, Dashtizadeh M,  Ishak M (2017). Mechanical 
and thermal properties of natural fibre based hybrid composites: a review. Pertanika Journal of Science 

and Technology 25(4):1103-1122.  

Della VP, Kühn I, Hotza D (2002). Rice husk ash as an alternate source for active silica production. Materials 

Letters 57(4):818-821.  

Deshmukh P, Peshwe D, Pathak S (2012). FTIR and TGA analysis in relation with the% crystallinity of the SiO2 

obtained by burning rice husk at various temperatures. Advanced Materials Research 585:7781. Trans 
Tech Publications Ltd.  

Diraddo  RW,  Laroche I (1995). Physical properties of virgin HDPE and recycled polymers. Plastics, Plastics, 

Rubber and Composites Processing and Applications 4(24):197-200.  

Dominic CDM, Begum PMS, Joseph R, Jose AR (2014). Rice Husk Silica-Efficient Bio Filler in High Density 

Polyethylene. International Journal of Advanced Scientific and Technical Research 4(2):561-569.  

Farooque KN, Zaman M, Halim E, Islam S, Hossain M, Mollah Y A, Mahmood AJ (2009). Characterization and 

utilization of rice husk ash (RHA) from rice mill of Bangladesh. Bangladesh Journal of Scientific and 
Industrial Research 44(2):157-162.  

Ghasemi Z, Younesi H (2011). Preparation and Characterization of Nanozeolite NaA from Rice Husk at Room 
Temperature without Organic Additives. Journal of Nanomaterials P 50.  

Ginting EM, Bukit N, Frida E (2017). Preparation and Characterization Of Nano Composites Hdpe Blend with 

Rice Husk Ash Nanoparticles. International Journal of ChemTech Research 10(13):348-356.  

Ginting EM, Wirjosentono B, Bukit N, Agusnar H (2014). Preparation and Characterization of Rice Husk Ash as 

Filler Material into  

Nanoparticles on HDPE Thermoplastic Composites. Journal Chemistry and Materials Research 6(7).  

 Govindarao VMH (1980). Utilization of rice husk: a preliminary analysis. Journal of Scientific and Industrial 
Research 39(9):495-515  

Johar N, Ahmad I, Dufresne A (2012). Extraction, preparation and characterization of cellulose fibres and 
nanocrystals from rice husk. Industrial Crops and Products 37(1):93-99.  

mailto:topacademicjournals@gmail.com


    

 Academic Journal of Science, Engineering and Technology 
Vol. 9, Issue 1; January - February 2024; 

ISSN: 2837-2964 

Impact Factor: 6.67 

1252 Columbia Rd NW, Washington DC, United States 

https://topjournals.org/index.php/AJSET/index; mail: topacademicjournals@gmail.com 

 

 

 

 

25 | A c a d e m i c  J o u r n a l  o f  S c i e n c e ,  E n g i n e e r i n g  a n d  T e c h n o l o g y  

|  https://topjournals.org/index.php/AJSET 

 

Hadi JA, Najmuldeen FG, Ahmed I (2014). Quality restoration of waste polyolefin plastic material through the 
dissolution-reprecipitation technique. Chemical Industry and Chemical Engineering Quarterly 20(2):163-

170. 

Hahladakis JN, Velis CA, Weber R, Iacovidou E,  Purnell P (2018). An overview of chemical additives presents 
in plastics: migration, release, fate and environmental impact during their use, disposal and recycling. 

Journal of hazardous materials 344:179-199.  

Khalil HA, Ismail H, Rozman HD, Ahmad MN (2001). The effect of acetylation on interfacial shear strength 

between plant fibres and various matrices. European Polymer Journal 37(5):1037-1045.  

Khan JH, Ahmed N (2003). Photo-oxidative degradation of recycled, reprocessed HDPE: changes in chemical, 

thermal and mechanical properties. Bulgarian Journal of Physics 30(3-4):158-169.  

Kohl JG, Kohl AG, Licea-Claverie A, Zizumbo-Lopez A, Jayasinghe R, Ashokcline M, Baillie C (2020). 

Mechanical and thermal characterization of as-received recycled polyethylene filled with rice husk and 

their relationship to the end use of these composites. Polymer-Plastics Technology and Materials 
59(13):1463-1472.  

Lei Y, Wu Q, Yao F,  Xu Y (2007). Preparation and properties of recycled HDPE/natural fiber composites. 
Composites Part A: applied science and manufacturing 38(7):1664-1674.  

Li Y, Hu C, Yu Y (2008). Interfacial studies of sisal fiber reinforced high density polyethylene (HDPE) 
composites. Composites Part A: Applied Science and Manufacturing 39(4):570-578.  

Lin JH, Pan YJ, Liu CF, Huang CL, Hsieh CT, Chen CK,  Lou CW (2015). Preparation and Compatibility 
Evaluation of Polypropylene/ High Density Polyethylene Polyblends. Materials 8(12):8850-8859.  

Mohamad FZC (2007). Performance of Recycled High Density Polyethylene (HDPE)/Rice Husk Composite 

Injection Grade in Thermoforming Process.  

Montanheiro TLDA, Passador FR, Oliveira MPD, Durán N,  Lemes AP (2016). Preparation and Characterization 

of Maleic Anhydride Grafted Poly (Hydroxybutirate-CO-Hydroxyvalerate)–PHBV-g-MA. Materials 
Research 19(1):229-235.  

Ng WK, Johar M, Israr HA, Wong KJ (2020). A review on the interfacial characteristics of natural fibre reinforced 
polymer composites. Interfaces in Particle and Fibre Reinforced Composites pp. 163-198.  

Parvinzadeh M, Moradian S, Rashidi A, Yazdanshenas ME (2010). Surface characterization of polyethylene  

 

mailto:topacademicjournals@gmail.com

