Restricted accessResearch articleFirst published online 2025
Preparation and characterization of a high-density polyethylene/date seed (HDPE/DS) composites: Effect of particle size,content,and chemical treatment of the DS powder filler on composite properties
This study focuses on developing and characterizing high-density polyethylene (HDPE) composites with date seed (DS) fillers. Untreated DS (UDS) and alkali-treated DS (TDS) fillers were incorporated at 10, 20, and 30 wt% using two-roll mixing and compression molding, and their structural, rheological, mechanical, physical, and morphological properties were systematically characterized. Structural analysis by Fourier-transform infrared spectroscopy (FTIR) confirmed the removal of hemicellulose and lignin in treated fillers, enhancing filler–matrix compatibility. Rheological testing showed a decrease in melt flow index with increasing filler content, which was more pronounced in TDS composites due to stronger interfacial interactions. Mechanically, HDPE/TDS composites exhibited a ∼28% increase in tensile strength, a ∼35% improvement in Young’s modulus, and a ∼22% enhancement in impact resistance compared to neat HDPE. In contrast, elongation at break decreased, reflecting the trade-off between stiffness and ductility. Physically, water absorption decreased by nearly 65% in TDS composites compared to UDS counterparts, while density showed slight improvement due to reduced porosity and enhanced cohesion. Morphological analysis confirmed more homogeneous, uniform filler dispersion, and reduced agglomeration in TDS-based composites compared to HDPE/UDS composites. Overall, chemical treatment of DS significantly enhanced the structural, rheological, mechanical, and physical properties of HDPE composites. These findings demonstrate the potential of treated date seed as a sustainable reinforcement material for future industrial applications.
MejiaECherupurakalNMouradA-HI, et al.Effect of processing techniques on the microstructure and mechanical performance of high-density polyethylene. Polymers2021; 13(19): 3346.
2.
MasriTBenchabaneAKaciA, et al.Date palm seeds waste in Algeria: mechanical characterization of epoxy/date palm seed composites. J Compos Adv Mater2025; 1: 1–11.
3.
MahmudMZARabbiSMFIslamMD, et al.Synthesis and applications of natural fiber‐reinforced epoxy composites: a comprehensive review. SPE Polymers2025; 6: e10161.
4.
Al-MosawiAIAbdulsadaSAHashimAA. Sustainable procedure for using waste of date seeds as a reinforcement material for polymeric composites. OAlib2018; 05(3): 1–9.
5.
MohammedMRasidiMMohammedA, et al.Interfacial bonding mechanisms of natural fibre-matrix composites: an overview. Bio2022; 17(4): 7031–7090.
6.
LatifRWakeelSZaman KhanN, et al.Surface treatments of plant fibers and their effects on mechanical properties of fiber-reinforced composites: a review. J Reinforc Plast Compos2019; 38(1): 15–30.
7.
AlnaidANorimanNZDahhamOS, et al.Effects of sodium hydroxide treatment on LLDPE/DS composites: tensile properties and morphology. J Phys : Conf Ser2018; 1019: 012061.
8.
SismanogluSTayfunUKanburY. Effect of alkali and silane surface treatments on the mechanical and physical behaviors of date palm seed-filled thermoplastic polyurethane eco-composites. J Thermoplast Compos Mater2022; 35(4): 487–502.
9.
RafiqahSADiyanaAFNAbdanK, et al.Effect of alkaline treatment on mechanical and thermal properties of miswak (Salvadora persica) fiber-reinforced polylactic acid. Polymers2023; 15(9): 2228.
10.
LawalNDanladiADaudaB, et al.The effect of alkali treatment on the mechanical properties of date seed particulates waste polypropylene filled composites. S.W.J2023; 18(3): 348–355.
11.
IsmailNFMohd RadzuanNASulongAB, et al.The effect of alkali treatment on physical, mechanical and thermal properties of kenaf fiber and polymer epoxy composites. Polymers2021; 13(12): 2005.
12.
RahmanMZHannanMAMollahMZI, et al.Evaluating physico-mechanical properties of NaOH-treated natural fibres: effects of polyolefin. Heliyon2024; 10(21): e39673.
13.
AlnaidANorimanNZDahhamOS, et al.Effects of date seeds size and loading on properties of linear low-density polyethylene/date seeds powder composites. J Phys : Conf Ser2018; 1019: 012060.
14.
AlnaidANorimanNZSamST, et al.The effects of different content and size of date seeds filler on thermal properties of LLDPE/date seeds (DS) composites. AIP Conf Proc2030; 2030: 020024.
15.
AlnaidANorimanNZSamST, et al.Study of fillers treatment using NaOH on the thermal properties of LLDPE/date seeds (DS) composites. In: Study of fillers treatment using NaOH on the thermal properties of LLDPE/date seeds (DS) composites. AIP Conf Proc, 2018, vol 2030, p. 020025.
16.
ElkhoulyHIA RushdiMK Abdel-MagiedR. Eco-friendly date-seed nanofillers for polyethylene terephthalate composite reinforcement. Mater Res Express2020; 7: 025101.
17.
ElkhoulyHI. Comparison of the effects of nano date seed as reinforcement material for medium-density polyethylene (MDPE) and polyethylene terephthalate (PET) using multilevel factorial design. Polym Polym Compos2021; 29: 1462–1471.
18.
MaouSMeghezziAGrohensY, et al.Effect of various chemical modifications of date palm fibers (DPFs) on the thermo-physical properties of polyvinyl chloride (PVC)–High-Density polyethylene (HDPE) composites. Ind Crops Prod2021; 171: 113974.
19.
OtaruAJ. Kinetics study of the thermal decomposition of date seed Powder/HDPE plastic blends. Bioresour Technol Rep2025; 29: 102028.
20.
Albin ZaidZAAOtaruAJ. Low-heating-rate thermal degradation of date seed powder and HDPE plastic: machine learning CDNN, MLRM, and thermokinetic analysis. Polymers2025; 17(6): 740.
ElobuikeAC. Effect of date seed powder filler on properties of high-density polyethylene: Ahmadu Bello University, 2017, pp. 1–109.
23.
ChafidzARizalMRmF, et al.Processing and properties of high density polyethylene/date palm fiber composites prepared by a laboratory mixing extruder. J Mech Eng Sci2018; 12(3): 3771–3785.
24.
AnbupalaniMSVenkatachalamCDRathanasamyR. Influence of coupling agent on altering the reinforcing efficiency of natural fibre-incorporated polymers – a review. J Reinforc Plast Compos2020; 39(13-14): 520–544.
25.
ElkhoulyHIAbdel-MagiedRKAlyMF. An investigation of date palm seed as effective filler material of glass–epoxy composites using optimization techniques. Polym Polym Compos2020; 28: 541–553.
26.
TunaSŞenİ. Characterization of olive seed powder incorporated low density polyethylene composites. SAUJS2025; 29(1): 71–82.
27.
Al-KhaliliMAl-HabsiNAl-AlawiA, et al.Structural characteristics of alkaline treated fibers from date-pits: residual and precipitated fibers at different pH. Bioact. Carbohydr. Diet. Fibre2021; 25: 100251.
28.
ElnaidANorimanNZDahhamOS, et al.Effects of sodium hydroxide treatment on date seeds reinforced LLDPE composites: FTIR and gel content analyses. In: BaghdadI (ed). Effects of sodium hydroxide treatment on date seeds reinforced LLDPE composites: FTIR and gel content analyses. AIP Conf Proc, 2020, vol 2213, p. 020268.
29.
MittalVChaudhryAUMatskoNB. “True” biocomposites with biopolyesters and date seed powder: mechanical, thermal, and degradation properties. J Appl Polym Sci2014; 131(19): app.40816.
30.
AugustiaVChafidzASetyaningsihL, et al.Effect of date palm fiber loadings on the mechanical properties of high density polyethylene/date palm fiber composites. KEM2018; 773: 94–99.
31.
AppuSPAshwaqOAl-HarthiM, et al.Fabrication and characterization of composites from recycled polyethylene and date palm seed powder. J Thermoplast Compos Mater2021; 34(3): 316–327.
32.
KhanSHDhakalHNSaifullahA, et al.Improved mechanical and thermal properties of date palm microfiber-reinforced PCL biocomposites for rigid packaging. Molecules2025; 30(4): 857.
33.
MarzoukWBettaiebFKhiariR, et al.Composite materials based on low-density polyethylene loaded with date pits: mechanical and thermal characterizations. J Thermoplast Compos Mater2017; 30(9): 1200–1216.
34.
OudianiAEChaabouniYMsahliS, et al.Crystal transition from cellulose I to cellulose II in NaOH treated Agave Americana L. fibre. Carbohydr Polym2011; 86(3): 1221–1229.
35.
ThandavamoorthyRDevarajanYThanappanS. Analysis of the characterization of NaOH-Treated natural cellulose fibre extracted from banyan aerial roots. Sci Rep2023; 13: 12579.
36.
MittalAKatahiraRHimmelME, et al.Effects of alkaline or liquid-ammonia treatment on crystalline cellulose: changes in crystalline structure and effects on enzymatic digestibility. Biotechnol Biofuels2011; 4: 41.
37.
BekeleAELemuHGJiruMG. Study of the effects of alkali treatment and fiber orientation on mechanical properties of enset/sisal polymer hybrid composite. J Compos Sci2023; 7(1): 37.
38.
VermaDGohKL. Effect of mercerization/alkali surface treatment of natural fibres and their utilization in polymer composites: mechanical and morphological studies. J Compos Sci2021; 5(7): 175.
39.
FuJHeCJiangC, et al.Degradation resistance of alkali-treated eucalyptus fiber reinforced high density polyethylene composites as function of simulated sea water exposure. Res2019; 14(3): 6384–6396.
40.
KamaruddinZJumaidinRIlyasR, et al.Influence of alkali treatment on the mechanical, thermal, water absorption, and biodegradation properties of cymbopogan citratus fiber-reinforced, thermoplastic cassava starch–Palm wax composites. Polymers2022; 14(14): 2769.
41.
ThenYYIbrahimNAZainuddinN, et al.Static mechanical, interfacial, and water absorption behaviors of alkali treated oil palm mesocarp fiber reinforced poly(butylene succinate) biocomposites. Bio.Ress2014; 10(1): 123–136.
42.
Ait BenhamouABoussettaANadifiyineM, et al.Effect of alkali treatment and coupling agent on thermal and mechanical properties of Opuntia ficus-Indica cladodes fibers reinforced HDPE composites. Polym Bull2022; 79: 2089–2111.
43.
Noor ZuhairaAAMohamedR. Comparison of melt flow and mechanical properties of rice husk and Kenaf hybrid composites. AMR (Adv Magn Reson)2013; 701: 42–46.
44.
GhazanfariAEmamiSPanigrahiS, et al.Thermal and mechanical properties of blends and composites from HDPE and date pits particles. J Compos Mater2008; 42(1): 77–89.
45.
JayaHOmarMFMd AkilH, et al.Effect of particle size on mechanical properties of sawdust-high density polyethylene composites under various strain rates. Res2016; 11(3): 6489–6504.
46.
AlghamdiMN. Effect of filler particle size on the recyclability of fly ash filled HDPE composites. Polymers2021; 13(16): 2836.
47.
SirajSAl-MarzouqiAHIqbalMZ, et al.Impact of micro silica filler particle size on mechanical properties of polymeric based composite material. Polymers2022; 14(22): 4830.
48.
GovernmentRMNgabeaSA. Effect of particle size and filler content on mechanical properties of avocado wood flour-low density polyethylene composite. Jasem2023; 27(10): 2303–2313.
49.
BosanBMBintaHAdejoOH, et al.National metallurgical development centre, jos, effect of particle size and filler content on some properties of recycled low density polyethylene/periwinkle shell composite. IJERT2020; V9: IJERTV9IS020019.
50.
AhmadIMahanwarPA. Mechanical properties of fly ash filled high density polyethylene. Composites Part B: Engineering2010; 09: 183–198.
51.
SiderINassarMMA. Chemical treatment of bio-derived industrial waste filled recycled low-density polyethylene: a comparative evaluation. Polymers2021; 13(16): 2682.
52.
Mechanical properties of polyethylene filled with treated neuburg siliceous Earth. Technical Transactions, 2018.
53.
AlsewailemFDBinkhderYA. Preparation and characterization of polymer/date pits composites. J Reinforc Plast Compos2010; 29(11): 1743–1749.
54.
Abdul AzamFARajendran RoyanNRYuhanaNY, et al.Fabrication of porous recycled HDPE biocomposites foam: effect of rice husk filler contents and surface treatments on the mechanical properties. Polymers2020; 12(2): 475.
55.
AbdelkaderAGueriraBBoussehelH, et al.Effect of advanced chemical treatments on the tensile and bending properties of date palm composites. RCMA2024; 34(2): 195–205.
56.
CurtoMLe GallMCatarinoAI, et al.Long-term durability and ecotoxicity of biocomposites in marine environments: a review. RSC Adv2021; 11: 32917–32941.
57.
LekrineABelaadiABoumaazaM, et al.Water absorption of industrial high-density polyethylene biocomposites reinforced with Washingtonia filifera fibers: optimization using fick’s, RSM, and ANN models2022.
58.
BelgacemCSerra-PararedaFTarrésQ, et al.The integral utilization of date palm waste to produce plastic composites. Polymers2021; 13(14): 2335.
59.
ZabihzadehSM. Effect of lignocellulosic type on long-term hygroscopic behavior of natural Filler/HDPE composites. J Polym Environ2011; 19: 133–136.
60.
ChenRSChaiYHOluguEU, et al.Evaluation of mechanical performance and water absorption properties of modified sugarcane bagasse high-density polyethylene plastic bag green composites. Polym Polym Compos2021; 29: S1134–S1143.
61.
ZabihzadehSM. Water uptake and flexural properties of natural Filler/HDPE composites. Bio2009; 5: 316–323.
62.
LiXTabilLGPanigrahiS. Chemical treatments of natural fiber for use in natural fiber-reinforced composites: a review. J Polym Environ2007; 15: 25–33.
63.
GassanJBledzkiAK. Possibilities for improving the mechanical properties of jute/epoxy composites by alkali treatment of fibres. Compos Sci Technol1999; 59: 1303–1309.
64.
AlshammariBAAlenadAMAl-MubaddelFS, et al.Impact of hybrid fillers on the properties of high density polyethylene based composites. Polymers2022; 14(16): 3427.
65.
NajafiAKhademi-EslamH. Lignocellulosic filler/recycled HDPE composites: effect of filler type of physical and flexural properties. Bio2011; 6(3): 2411–2424.
66.
BledzkiA. Composites reinforced with cellulose based fibres. Prog Polym Sci1999; 24: 221–274.
67.
GeorgeJSreekalaMSThomasS. A review on interface modification and characterization of natural fiber reinforced plastic composites. Polym Eng Sci2001; 41: 1471–1485.
68.
JohnMThomasS. Biofibres and biocomposites. Carbohydr Polym2008; 71: 343–364.
69.
AlawarAHamedAMAl-KaabiK. Characterization of treated date palm tree fiber as composite reinforcement. Compos B Eng2009; 40: 601–606.
70.
El-ShekeilYASapuanSMAbdanK, et al.Influence of fiber content on the mechanical and thermal properties of kenaf fiber reinforced thermoplastic polyurethane composites. Mater Des2012; 40: 299–303.
71.
SawpanMAPickeringKLFernyhoughA. Effect of various chemical treatments on the fibre structure and tensile properties of industrial hemp fibres. Compos Appl Sci Manuf2011; 42: 888–895.
72.
PatsiaouraDTaraniEBikiarisDN, et al.Lignocellulosic-Based/High density polyethylene composites: a comprehensive study on fiber characteristics and performance evaluation. Appl Sci2024; 14(9): 3582.
73.
HuangRXuXLeeS, et al.High density polyethylene composites reinforced with hybrid inorganic fillers: morphology, mechanical and thermal expansion performance. Mater2013; 6(9): 4122–4138.
