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A review of weathering studies in plastics and biocomposites— Effects on mechanical properties and emissions of volatile organic compounds (VOCs)
(2024-04) Nzimande, Monwabisi C; Mtibe, Asanda; Tichapondwa, S; Mathew, Maya J
Polymeric materials undergo degradation when exposed to outdoor conditions due to the synergistic effects of sunlight, air, heat, and moisture. The degradation can lead to a decline in mechanical properties, fading, surface cracking, and haziness, attributed to the cleavage of the polymer chains and oxidation reactions. Accelerated weathering testing is a useful technique to evaluate the comparative photodegradation of materials within a reasonable timeframe. This review gives an overview of the different degradation mechanisms occurring in conventional plastics and bio-based materials. Case studies on accelerated weathering and its effect on the mechanical properties of conventional plastics and biocomposites are discussed. Different techniques for analysing volatile organic emissions (VOCs) have been summarized and studies highlighting the characterization of VOCs from aged plastics and biocomposites after aging have been cited.
Advancements in antimicrobial textiles: Fabrication, mechanisms of action, and applications
(2025) Orasugh, JT; Temane, Lesego Y; Pillai, Sreejarani K; Ray, Suprakas S
Within the past decade, much attention has been drawn to antimicrobial textiles due to their vast potential for reducing the spread of infectious diseases and improving hygiene standards in various environments. This review paper discusses recent studies on preparation methods, modes of action, effectiveness against different microorganisms, and applications of antimicrobial textiles in diverse industries. It examines further challenges, including durability, environmental impact, and regulatory considerations, and looks at prospects for developing and integrating these novel materials. This paper intends to provide a broad-based understanding of state-of-the-art technologies and emerging trends in antimicrobial textiles by integrating existing knowledge and highlighting recent advances in this field that contribute much to improved public health and safety.
Algae infused enhancement of PBAT stiffness: Investigating the influence of algae content on mechanical and thermal properties
(2024) Letwaba, J; Motloung, Mpho P; Muniyasamy, Sudhakar; Mavhungu, L; Mbaya, R; Okpuwhara, R
This study investigates the impact of algae loading on the properties of PBAT/algae bio-composites produced through a melt extrusion process. The integration of algae as a filler demonstrated a reinforcing effect on the PBAT matrix,leading to an increase in modulus with higher algae loading. Concurrently, the tensile strength and maximum tensile strain of PBAT decreased with an increase in algae content. The thermal stability of PBAT was affected by adding algae, resulting in bio-composites exhibiting an intermediate behavior compared with their neat precursors. The optimal formulation is achieved with 20 wt.% of algae incorporated into the PBAT matrix. The produced PBAT/algae bio-composites, demonstrated versatile applications across a wide range of products.
Antibiotic 3D printed Materials for healthcare applications
(Elsevier Inc, 2020-05) Mokhena, Teboho C; John, Maya J; Mochane, MJ; Sadiku, ER; Motsoeneng, TS; Mtibe, Asanda; Tsipa, PC; Kokkarachedu, V; Kanikireddy, V; Sadiku, R
Since its introduction in the past 25 years, three-dimensional (3D) printing has been a major research topic owing to its potential to overcome the limitations of conventional 3D manufacturing techniques, that is, to control the overall architecture toward various applications. In the third (2013–present) decade, 3D printing enters a new phase in which researchers fabricate clinical constructs that benefit the current society. In this chapter, we briefly discuss the recent progress of 3D printing and challenges related to the antibiotic materials and manufacturing process for biomedical applications.
Application of electrospun materials in oil–water separations
(Scrivener Publishing LLC, 2020-04) Mokhena, Teboho C; John, Maya J; Mochane, MJ; Tsipa, PC; Boddula, RI; Ahamed, MI; Asiri, AM
There has been ever-increasing pressure to come up with novel strategies for oily wastewater treatment since it affect the available water sources, crop production, aquatic life and human health. Electrospun nanofibrous materials with attractive attributes, such as interconnected porous structure, large surface-to-area ratio, malleable mechanical properties, tuneable wettability, and porosity have a huge potential for oily wastewater treatment. In this chapter, the recent progress of oil/ water separation using electrospun nanofibrous materials is reviewed. The challenges and future prospects of this new field are also described.
Bio-composite films from carrageenan/starch reinforced with nanocellulose for active edible food packaging: Development and optimization
(2025) Dmitrenko, M; Pasquini, D; Piassi Bernardo, M; De Lima Alves, JM; Kuzminova, A; Dzhakashov, I; Terentyev, A; Joshy, KS; Maya, Mathew J; Dyachkov, A
Petrochemical plastics are widely used for food protection and preservation; however, they exhibit poor biodegradability, resisting natural degradation through physical, chemical, or enzymatic processes. As a sustainable alternative to conventional plastic packaging, edible films offer effective barriers against moisture, gases, and microbial contamination while being biodegradable, biocompatible, and environmentally friendly. In this study, novel active food packaging materials (in film form) were developed by incorporating starch, carrageenan, nanocellulose (NC), Aloe vera, and hibiscus flower extract. The effects of varying the matrix composition (26.5–73.5 wt.% starch/carrageenan), NC concentration (2.77–17.07 wt.%), and particle type (fibers or crystals) on the film structure and characteristics were analyzed using various methods. Scanning electron microscopy demonstrated good homogeneity and effective dispersion of NC within the blend matrix. An increased carrageenan content in the film improved wettability, moisture absorption, solubility, and water vapor permeability. The mechanical properties of the films were enhanced by NC incorporation and higher carrageenan content. The developed films also exhibited effective UV radiation barriers and biodegradability. Films with low carrageenan content (less than 33.3%) and high NC content (7%, 10% crystals or 10%, 15% fibers) exhibited optimal properties, including enhanced water resistance, hydrophobicity, and mechanical strength, along with reduced water vapor permeability. However, the high water solubility and moisture absorption (above 55% and 14%, respectively) indicated their unsuitability as packaging materials for food products with wet surfaces and high humidity. Theresults suggest that these films are well suited for use as edible food packaging for fruits and vegetables.
Biobased Biodegradable Polybutylene Succinate Polymers and Composites: Synthesis, Structure Properties and Applications—A Review
(2025) Makgwane, Peter R; Muniyasamy, Sudhakar; Hlekelele, Lerato; Swanepoel, Andri; Sypu, Venkata S; Mdlalose, Lindani M; Naidoo, Saloshee; Cele, Zamani; Maity, Arjun; Balogun, Mohammed O; Botlhoko, OJ
The materialization of polybutylene succinate (PBS) belongs to the family of polyesters which are degradable and biodegradable, their biodegradability properties have attracted enormous interest for product development towards different polymer-based applications. Besides its biodegradability, PBS can be derived from petroleum and biobased monomers. At the same time, the latter is the driving factor for its growing interest in bioplastics for fully green and sustainable biobased-derived polymer products. The processes and techniques presented herein, are based on the production of biobased succinic acid monomer to PBS. However, the counterpart biobased monomer 1,4-butanediol (1,4-BDO) production has not been commercially demonstrated. This review discusses the progress in state-of-the-art developments in the synthesis strategies of PBS, its copolymers, and composites with the view to improve molecular weight, thermal, and mechanical properties. It further analyzes the different strategies to synthesize modified PBS polymer composites from organic and inorganic nanofillers to enhance their chemical, thermal, stability and mechanical structural properties. Importantly, the review highlights the progress in the applications of PBS copolymers and composites with tailored structure-designed properties for specific sectors such as packaging films, biomedical and drug release, fire retardants, and agricultural products. The structure-functional performance characteristics of these developments in the PBS, copolymers, and composites are highlighted to provide baseline insights for future developments in engineering the specific applications, and structural interface PBS composites with enhanced structure-functional performance properties.
Bioelectricity generation by natural microflora of septic tank wastewater (STWW) and biodegradation of persistent petrogenic pollutants by basidiomycetes fungi: An integrated microbial fuel cell system
(2021-01) Thulasinathan, B; Jayabalan, T; Sethupathi, M; Kim, W; Muniyasamy, Sudhakar; Sengottuvelan, N; Nainamohamed, S; Ponnuchamy, K; Alagarsamy, A
The microbial fuel cell is a unique advantageous technology for the scientific community with the simultaneous generation of green energy along with bioelectroremediation of persistent hazardous materials. In this work, a novel approach of integrated system with bioelectricity generation from septic tank wastewater by native microflora in the anode chamber, while Psathyrella candolleana with higher ligninolytic enzyme activity was employed at cathode chamber for the biodegradation of polycyclic aromatic hydrocarbons (PAHs). Six MFC systems designated as MFC1, MFC2, MFC3, MFC4, MFC5, and MFC6 were experimented with different conditions. MFC1 system using natural microflora of STWW (100%) at anode chamber and K3[Fe(CN)6] as cathode buffer showed a power density and current density of 110 ± 10 mW/m2 and 90 ± 10 mA/m2 respectively. In the other five MFC systems 100% STWW was used at the anode and basidiomycetes fungi in the presence or absence of individual PAHs (naphthalene, acenaphthene, fluorene, and anthracene) at the cathode. MFC2, MFC3, MFC4, MFC5, and MFC6 had showed power density of 132 ± 17 mW/m2, 138 ± 20 mW/m2, 139 ± 25 mW/m2, and 147 ± 10 mW/m2 respectively. MFC2, MFC3, MFC4, MFC5, and MFC6 had showed current density of 497 ± 17 mA/m2, 519 ± 10 mA/m2, 522 ± 21 mA/m2 and 525 ± 20 mA/m2 respectively. In all the MFC systems, the electrochemical activity of anode biofilm was evaluated by cyclic voltammetry analysis and biofilms on all the MFC systems electrode surface were visualized by confocal laser scanning microscope. Biodegradation of PAHs during MFC experimentations in the cathode chamber was estimated by UV-Vis spectrophotometer. Overall, MFC6 system achieved maximum power density production of 525 ± 20 mA/m2 with 77% of chemical oxygen demand removal and 54% of coulombic efficiency at the anode chamber and higher anthracene biodegradation (62 ± 1.13%) at the cathode chamber by the selected Psathyrella candolleana at 14th day. The present natural microflora - basidiomycetes fungal coupled MFC system offers excellent opening towards the simultaneous generation of green electricity and PAHs bioelectroremediation.
Cellulose nanocrystals-based composites
(Scrivener Publishing LLC, 2020-01) Mokhena, Teboho C; John, Maya J; Mochane, MJ; Mtibe, Asanda; Motsoeneng, TS; Mokhothu, TH; Tshifularo, CA; Jamil, N; Kumar, P; Batool, R
Cellulose nanocrystals and cellulose nanocrystals-based composites with their unique features, such as abundance, renewability, high strength and stiffness, eco-friendliness, and relatively low density received unprecedented interest from both academia and industries as replacement of conventional petroleum-based materials, since conventional petroleum-based materials create ecological threats such as global warming and pollution. In this chapter, critical factors in the manufacturing of cellulose nanocrystals-based composites with regard to preparation methods, morphology, barrier and mechanical behaviour are comprehensively discussed. It concludes with the recent developments and future trends of cellulose nanocrystals reinforced biopolymers.
Cellulose nanomaterials: New generation materials for solving global issues
(2020-02) Mokhena, Teboho C; John, Maya J
This review describes the recent advances in the production and application of cellulose nanomaterials. Cellulose nanomaterials (CNMs), especially cellulose nanocrystals and cellulose nanofibers, can be produced using different preparation processes resulting in materials with unique structures and physicochemical properties that are exploited in different fields such as, biomedical, sensors, in wastewater treatment, paper and board/packaging industry. These materials possess attractive properties such as large surface area, high tensile strength and stiffness, surface tailor-ability via hydroxyl groups and are renewable. This has been a driving force to produce these materials in industrial scale with several companies producing CNMs at tons-per-day scale. The recent developments in their production rate and their applications in various fields such as medical sector, environmental protection, energy harvesting/storage are comprehensively discussed in this review. We emphasize on the current trends and future remarks based on the production and applications of cellulose nanomaterials.
Design and development of cellulosic bionanocomposites from forestry waste residues for 3D printing applications
(2021-06) Mathew, Maya J; Dyanti, Nokuzola; Mokhena, Teboho C; Agbakoba, Victor; Sithole, Bishop B
This paper deals with the development of cellulose nanofibres (CNFs) reinforced biopolymers for use in packaging applications. Cellulose nanofibres were extracted from sawdust by a combination of chemical and mechanical treatments. The extracted cellulose nanofibres were chemically modified (fCNFs) and characterised by Fourier Transform Infrared Spectroscopy (FTIR). Bionanocomposites were prepared from biopolymers polylactic acid/polybutylene succinate (PLA/PBS) and cellulose nanofibres by compounding in a twin-screw extruder followed by injection moulding. The developed bionanocomposites were subjected to mechanical and thermal characterisation. As part of product development, CNF-biopolymer pellets were also extruded into filaments which were then 3D printed into prototypes. This work is a successful demonstration of conversion of waste residues into value-added.
Design of 3D printable boehmite alumina/thermally exfoliated reduced graphene oxide-based polymeric nanocomposites with high dielectric constant, mechanical and thermomechanical performance
(2024-09) Botlhoko, Orebotse J; Makwakwa, Dimakatso M; Muniyasamy, Sudhakar
In this study, melt-blending was employed to blend 80 wt% poly(lactic acid) and 20 wt% poly(ε-caprolactone) (80 %PLA/20 %PCL) with boehmite alumina-thermally exfoliated reduced graphene oxide (BA-TERGO) as nanofillers. Herein, we present a novel synergy effect of BA/TERGO particles on improving the dielectric constant while maintaining dielectric loss at lower magnitudes. Also, improving the thermomechanical properties of tough PLA/PCL nanocomposite through the incorporation of a dual-filer system strategy. Consequently, remarkable increase in dielectric constant was achieved for BA-TERGO/blend nanocomposite. In particular, the blend exhibited dielectric constant of about 2.91, while the BA-TERGO/blend nanocomposite exhibited dielectric constant of about 4.93 at a frequency of 2.0 ×106 Hz and a temperature of 190 ºC. On the other hand, tensile modulus of the BA-TERGO/blend nanocomposite increased from 1908.5 MPa to 2505.2 MPa and the tensile strength increased from 70.48 MPa to 96.3 MPa when compared to that of the neat blend. BA-blend and BA-TERGO/blend nanocomposites provided the improved storage modulus and thermal stability. This finding renders PLA-based biodegradable materials suitable for tough 3D printable material with potential for integrated circuits applications.
Effect of clay nanofillers on the mechanical and water vapor permeability properties of xylan–alginate films
(2020-10) Naidu, Darrel S; Mathew, Maya J
In this study, xylan–alginate-based films were reinforced with nanoclays (bentonite or halloysite) by the solvent casting technique. The effect of the nanoclay loadings (1–5 wt %) on various properties—mechanical, optical, thermal, solubility, water sorption, and water vapor permeability (WVP)—of the xylan–alginate films were examined for their application as food packaging materials. A 5 wt % loading of either bentonite or halloysite resulted in a 49% decrease of the WVP due to the impermeable nature of the silicate layers that make up both bentonite and halloysite. Thermal stability and solubility of the nanocomposite films were not significantly influenced by the presence of the nanoclays, whereas the optical properties were significantly improved when compared to neat xylan–alginate blend. In general, films reinforced with bentonite exhibited superior mechanical and optical properties when compared to both halloysite-based nanocomposite and neat films.
Elucidating the local structure and electronic properties of a highly active overall alkaline water splitting NixCo1-xO/hollow carbon sphere catalyst
(2024) Mashindi, V; Terban, MW; Motta Meira, D; Moreno, BD; Morongoa, Prettier M; Rikhotso-Mbungela, Rirhandzu S; Marx, G; Olivier, J; Barrett, DH; Moloto, N
A NixCo1-xO/HCS catalyst with superior water-splitting is presented. High water-splitting reaction kinetics and enhanced durability were observed. The structure-function relationship was investigated with XPS, which demonstrated the presence of dominant Ni2+ and Co2+ species and a functionalized HCS support where nucleation of small metal oxide nanoparticles occurred. The PDF showed broadened Nickel/Cobalt-oxide bonds and expansion of the metal-metal pair distances. The alteration of the Metal-Oxide and Metal-Metal-Oxide bonds favored better HER and OER electrocatalysis, also as supported by DFT. EXAFS showed the existence of the bimetallic oxide catalyst and the stretching of the Ni–O bonds due to the coordination of the Ni–O with the Co. The composite exhibited higher activity and enhanced electrocatalytic mechanism towards water splitting through higher exchange current densities (0.615 and 0.886 mA cm−2) and low charge transfer resistance (14 and 10 Ω) respectively. Chronoamperometry proved the catalyst's stability during prolonged electrolysis.
Engineered transparent wood composites: A review
(2023-05) Jele, Thabisile B; Andrew, Jerome E; Mathew, Maya J; Sithole, Bruce
Wood is a versatile resource due to its inherent properties such as low density, good weight to strength ratio, unique hierarchical structure, microscale pores, and ease of processing, including its biodegradability and renewability. In the building and construction industry, engineered transparent wood (ETW) may serve as a sustainable replacement for glass which is environmentally unfriendly in its manufacture and application. Natural wood is non transparent due to its low optical transmittance, therefore, lignin and chromophores are modified or eliminated, and a polymer is infiltrated in order to achieve transparency. Engineered transparent wood (ETW) exhibits excellent optical properties (transmittance>80%), high haze (haze>70%), thermal insulation (thermal conductivity less than 0.23Wm-1 K-1), unique hierarchical structure, good loadbearing performance with tough failure behaviour (no shattering) and ductility. These properties extend wood applications to optical components such as solar cells, screens, windows, magnetic materials, and luminescent and decorative materials. This review details the production of ETW and how the wood density, wood thickness, wood type, wood direction, cellulose volume fraction, extent and type of delignification, polymer type, functionalisation of ETW affect the morphological, functional, optical, thermal, photodegradation and mechanical properties of ETW.
Engineered transparent wood with cellulose matrix for glass applications: A review
(2024-06) Simelane, Nontobeko P; Olatunji, OS; Mathew, Maya J; Andrew, Jerome E
Engineered transparent wood (ETW), derived from the modification of natural wood, presents a sustainable and aesthetically pleasing alternative to traditional glass. This review comprehensively explores the burgeoning field of ETW as a novel material for applications in the glass industry. A comprehensive overview of the various methodologies employed in the engineering of transparent wood, encompassing delignification, polymer infiltration, and other innovative techniques is provided. Additionally, the optical, mechanical, and thermal properties of ETW are systematically examined, highlighting its potential advantages over conventional glass materials. The review also discusses recent advancements, challenges, and future considerations of ETW. Furthermore, the review discusses key applications in the glass industry where ETW has demonstrated promising performance, including windows, facades, and decorative elements. Essentially, this review aims to enhance understanding of ETW's potential in glass applications by critically analyzing current research and advancements. It seeks to pave the way for future developments in this innovative and eco-friendly technology.
Engineering γ-TiAl alloys: The effects of Sn, Si and Mn on densification, microstructure, and mechanical properties
(2025-06) Ellard, JJM; Mathabathe, Maria N; Siyasiya, CW; Bolokang, Amogelang S; Vilane, VN; Rikhotso-Mbungela, Rirhandzu S; McDuling, Christoffel P; Masete, Mosimanegape S
In the quest to enhance the castability of modified second-generation γ-TiAl intermetallic alloys and improve their mechanical properties, the effects of small additions of Sn, Si, and Mn were investigated and compared in terms of densification, microstructural evolution, and corresponding mechanical properties. The alloys were produced by vacuum arc remelting of blended and cold-pressed precursor powders. The processing parameters were uniformly maintained for all the alloys. According to the results, the relative green density of quaternary-Si (Ti-48Al-2Nb-0.7Cr-0.3Si) compact was the highest with a value of 90.00 ± 0.07 %. The addition of 1 at.%Sn improved the castability of the alloy as indicated by the absence of shrinkage cavities and the highest relative density of 99.87 ± 0.06 %. However, after heat treatment, low values of room temperature yield strength (286 ± 23 MPa) and ultimate tensile strength (486 ± 48 MPa) were obtained as the Sn promoted the growth of γ grains and hindered the nucleation of α 2 and Ti 5 Si 3 phases. Conversely, additions of 0.3 at.%Si and 0.3 at.% Mn did not improve the castability of the alloys. However, Si promoted the nucleation of Ti 5 Si 3 precipitates which improved the yield strength to 494 ± 31 MPa and uniform elongation to 1.4 ± 0.1 % after heat treatment. Additionally, the quaternary-Si alloy exhibited improved fatigue properties at room temperature with a fatigue limit of 388 MPa. Its fatigue fracture modes were Inter-lamellar and cleavage at lower stress amplitudes, σ fracture mode dominated at higher σ a. Mn promoted the nucleation of α 2 a, while inter-lamellar-phase to give a moderate value of 426 ± 19 MPa yield strength after heat treatment.
Esterified cellulose nanofibres from saw dust using vegetable oil
(2020-04) Mokoena, Teboho P; Mathew, Maya J
In this work, cellulose nanofibres (CNFs) were extracted from sawdust, which is an underutilized by-product from the wood and timber industry. The extracted CNFs by chemical and mechanical treatments had a web-like structure with diameters ranging between 2 nm and 27 nm and lengths reaching a few microns. The obtained CNFs were further chemically modified with vegetable canola oil using two different esterification processes. In order to compare the effect of the surface modification of CNFs, the nanopapers were prepared from their prospective suspensions through solvent evaporation method, and then characterize with Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA), UV-vis spectroscopy and tensile tester. FTIR results indicated that both methods led to a successful grafting of the long chain hydrocarbon structure onto the CNFs, and became more hydrophobic when compared to unmodified CNFs-based nanopapers. The crystallinity, mechanical, light transmittance and thermal properties were significantly affected primarily by the esterification method employed, thus the degree of substitution. It was found that high degree of substitution adversely affected the crystallinity, light transmittance, mechanical and thermal properties. The crystallinity decreased from 70% to <40% when the degree of substation was about 0.8.
Evaluation of Lippia scaberrima Sond. and Aspalathus linearis (Burm.f.) R. Dahlgren extracts on human CYP enzymes and gold nanoparticle synthesis: implications for drug metabolism and cytotoxicit
(2024-04) Kok, AM; Juvonen, R; Pasanen, M; Mandiwana, Vusani; Kalombo, Lonji; Ray, Suprakas S; Rikhotso-Mbungela, Rirhandzu S
Background Metabolism is an important component of the kinetic characteristics of herbal constituents, and it often determines the internal dose and concentration of these effective constituents at the target site. The metabolic profile of plant extracts and pure compounds need to be determined for any possible herb‑drug metabolic interactions that might occur. Methods Various concentrations of the essential oil of Lippia scaberrima, the ethanolic extract of Lippia scaberrima alone and their combinations with fermented and unfermented Aspalathus linearis extract were used to determine the inhibitory potential on placental, microsomal and recombinant human hepatic Cytochrome P450 enzymes. Furthermore, the study investigated the synthesis and characterization of gold nanoparticles from the ethanolic extract of Lippia scaberrima as a lead sample. Confirmation and characterization of the synthesized gold nanoparticles were conducted through various methods. Additionally, the cytotoxic properties of the ethanolic extract of Lippia scaberrima were compared with the gold nanoparticles synthesized from Lippia scaberrima using gum arabic as a capping agent. Results All the samples showed varying levels of CYP inhibition. The most potent inhibition took place for CYP2C19 and CYP1B1 with 50% inhibitory concentration (IC50) values of less than 0.05 µg/L for the essential oil tested and IC50‑values between 0.05 µg/L‑1 µg/L for all the other combinations and extracts tested, respectively. For both CYP1A2 and CYP2D6 the IC50‑values for the essential oil, the extracts and combinations were found in the range of 1 – 10 µg/L. The majority of the IC50 values found were higher than 10 µg/L and, therefore, were found to have no inhibition against the CYP enzymes tested. Conclusion Therefore, the essential oil of Lippia scaberrima, the ethanolic extract of Lippia scaberrima alone and their combinations with Aspalathus linearis do not possess any clinically significant CYP interaction potential and may be further investigated for their adjuvant potential for use in the tuberculosis treatment regimen. Furthermore, it was shown that the cytotoxic potential of the Lippia scaberrima gold nanoparticles was reduced by twofold when compared to the ethanolic extract of Lippia scaberrima.
Influence of nucleation and growth mechanisms on the heat deflection temperature of a reactively processed polypropylene nanocomposite
(2021-02) Bandyopadhyay, Jayita; Mekoa, Raphaahle C; Makwakwa, Dimakatso M; Skosana, Sifiso; Ray, Suprakas S
The development of a reactively processed polypropylene nanocomposite (PPNC) with consequential improvements in the heat deflection temperature (HDT), Vicat softening temperature (VST), and crystallization peak temperature (Tc) is reported herein. Neat PP without nanoclay was also reactively processed to elucidate the effects of fillers on the improvement in physical properties. The results show a considerable improvement in the HDT of PPNC (77.9 °C) compared to those of neat PP (62.6 °C) and reactively processed branched PP (BPP; 69.2 °C). Moreover, the Tc of PP in PPNC improved by ~14% compared to that of neat PP. Various models of nonisothermal crystallization kinetics were employed to elucidate the nucleation and crystal growth mechanisms, and to correlate them with the observed HDT improvement in PPNC. Thermal transitions investigated by modulated differential scanning calorimetry explained the changes observed in the VSTs of all the samples. To the best of our knowledge, this is the first report on a significant improvement in HDT along with a marked increase in Tc. Such simultaneous improvements in HDT, VST, and Tc are highly desirable for applications involving the use of PP-based materials in rigid packaging.

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