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Article

Reinforcement of Polyethylene with Potassium Hexatitanate Whiskers: Importance of Polyvinylpyrrolidone Additive

by
Qin Pan
1,2,3,
Qinxiang Jia
1,2,
Jin Xie
1,
Xiaoyong Li
1,2,3,
Yong Wu
1,2,*,
Yang Sun
1,2,3,
Suihong Chu
4,
Bo Yang
4,
Zhexi Chen
1 and
Kewei Peng
1
1
Department of Applied Chemistry, School of Chemistry, Xi’an Jiaotong Univeristy, Xi’an 710049, China
2
Xi’an Biomass Green Catalysis and Advanced Valorization International Science and Technology Cooperation Base, Xi’an 710049, China
3
Xingyi Advanced Materials Technology Co., Ltd., Xixian New District, Xi’an 712000, China
4
Shaanxi LESSO Technology Industrial Co., Ltd., Xianyang 713800, China
*
Author to whom correspondence should be addressed.
J. Compos. Sci. 2025, 9(1), 11; https://doi.org/10.3390/jcs9010011
Submission received: 6 September 2024 / Revised: 25 December 2024 / Accepted: 27 December 2024 / Published: 2 January 2025
(This article belongs to the Section Polymer Composites)
Browse Figures
Versions Notes

Abstract

:
Potassium hexatitanate whiskers are prepared and characterized in this study. The reinforcement of polyethylene with potassium hexatitanate whiskers is also investigated. The potassium hexatitanate whiskers are prepared through the calcination of TiO2 and K2CO3 at 1000 °C. It is determined that a polyvinylpyrrolidone additive is crucial for the formation of slender rod-like structures with smooth and flat surfaces and a high length-to-diameter ratio. For the surface modification of the whiskers, γ-aminopropyl triethoxysilane has been identified as the most effective coupling agent for enhancing mechanical properties. The whiskers have little change in shape after surface modification, and the majority of the whiskers still retain a considerable length-to-diameter ratio. The results of mechanical tests indicate that the tensile strength and the modulus of elasticity, as well as the shear strength and the shear elasticity, are enhanced to some extent. The tensile strength and the modulus of elasticity increase by 18.6% and 3.6%, respectively. The modified polyethylene composites show enhanced softness and elasticity. The elongation at the break for the prepared PE/PHT-2-1 composites increases significantly to 38.1%, significantly exceeding that of unfilled polyethylene (6.84%). Nevertheless, a suitable method is established for reinforcing thermoplastic polymers using inexpensive potassium hexatitanate whiskers.

Graphical Abstract

1. Introduction

Reinforcement plays a crucial role in enhancing the properties of composite materials. It is used not only to improve mechanical properties (tensile strength, hardness, modulus of elasticity, etc.), but also to modify thermal, electrical, magnetic and other properties. Commonly, materials used for reinforcement are categorized into three forms in shape: fibers, whiskers, and powders. Whiskers are characterized by their short, fiber-shaped, single-crystal structures with a large length-to-diameter ratio. Due to the perfect crystal structure, the mechanical strength of whiskers is very high and close to the force of the interatomic bond [1]. Whiskers are therefore regarded as a novel class of materials for reinforcement in composite materials.
The family of potassium titanates, K2O·nTiO2 (n = 1, 2, 4, 6 or 8), comprises a series of compounds [2,3,4,5,6,7,8,9,10,11,12,13,14]. They have been recognized as important materials for different applications, and their properties vary with the value of n [15,16,17,18,19]. When n = 6, it is referred to as potassium hexatitanate (PHT). The crystal structure consists of chains of Ti octahedra (TiO6), sharing edges and corners with some tunnels where the K ions can fit. As shown in Figure 1, the space group is C2/m, and the cell contains 2(K2Ti6O13) [20]. This type of structure is conductive to whisker growth [21,22,23,24,25,26], providing for different applications such as for photocatalysts [27,28,29,30,31,32,33], thermal insulators [34,35], optical materials [36,37], reinforcement agents [38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54], etc. PHT whiskers are notable for their high thermal stability (ca. 1200 °C) and low density. They show high resistance to volume change under stress. Moreover, PHT whiskers are softer than other reinforcement agents such as SiC, favoring manufacturing them for the preparation of composite materials with ordinary tools.
Thermoplastic polymers, widely utilized globally, often incorporate reinforcement agents to reduce manufacturing costs or enhance properties. Various inorganic whiskers, such as calcium carbonate, aluminum oxide, and potassium titanate, have been employed in thermoplastic matrices. It has been demonstrated that the whiskers can reinforce thermoplastic more effectively than short-glass or carbon fibers [51]. For instance, Yu and coworkers reported the dielectric and mechanical properties of a polypropylene–polyamide (PP/PA) blend with the reinforcement of potassium titanate whiskers [34]. The whisker surface was modified by a silane or a titanate coupling agent. It was shown that both whisker-surface modification and the corresponding coupling agent could strongly affect the properties. Both the mechanical and dielectric properties were improved with the number of whiskers (<20 phr). It was revealed that the composite had a continuous PP phase and a dispersed PA phase, and that the whiskers were embedded in the PA particles exclusively. Ou et al. investigated the interfacial interaction of nylon 6-potassium titanate composites [52]. It was found that the modification of the whisker surface with a silane coupling agent is very important, to increase interfacial interactions and improve mechanical properties. Hao et al. used potassium titanate whiskers to reinforce PA66 composites and investigated their quasi-static and dynamic mechanical properties [53]. Qu and coworkers reported the performance of potassium titanate whiskers on the reinforcement of poly(phthalazinone ether sulfone ketone) (PPESK) composites [54]. The results showed that the tensile strength and impact strength of the composites increased with the content of whiskers (10–20 phr), and a decrease was found for a whisker content of 40 phr. Additionally, thermal conductivity was found to be influenced and dependent on the filler fraction in polymer composite materials [55].
In this work, we attempted to use PHT to reinforce polyethylene (PE) composites. PE, a lightweight thermoplastic polymer built from ethylene polymerization, is non-toxic, inexpensive, and extensively used in applications such as pipelines and packaging. Depending on the molecular structures and weights, it can be classified into different types, such as low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), medium-density polyethylene (MDPE), high-density polyethylene (HDPE), and ultra-high-molecular-weight polyethylene (UHMWPE). These variations provide a wide range of mechanical properties, facilitating the fine-tuning of desired material properties. Among these, UHMWPE has high strength, high resistance to abrasion and cracking, high biocompatibility, and high resistance to low temperatures. However, it is often necessary to form composites to achieve desired properties for practical applications. For example, the tensile strength and modulus of elasticity are required to be specific desired values in pipelines.
The small size of potassium titanate whiskers tends to cause agglomeration, and hydrophilicity can hinder strong interactions with polymers. Therefore, selecting an appropriate coupling agent to modify the whisker surface is critical for enhancing dispersion and interaction, thereby optimizing reinforcement performances. In this study, we characterized the prepared PHT whiskers and composites, and comparatively analyzed their mechanical properties. The effects of additives and coupling agents, specifically γ-aminopropyl triethoxysilane (KH-550), γ-glycidoxypropyl trimethoxysilane (KH-560), and γ-methacryloxypropyl trimethoxy silane (KH-570), were determined in this work.

2. Materials and Methods

2.1. Materials

Titanium dioxide (TiO2), anhydrous potassium carbonate (K2CO3), polyvinylpyrrolidone (PVP, average molecular mass, ~58,000), KH-550, KH-560, and KH-570 coupling agents, and anhydrous ethanol, were purchased from Shanghai Yien Chemical Technology Co., Ltd., Shanghai, China. UHMWPE was acquired from LESSO Technology Industrial Co., Ltd., Foshan, China. All reagents were used directly without further processing.

2.2. Preparation of PHT Whiskers

For the preparation of PHT whiskers, synthesis methods included calcination, flux growth, hydrothermal reaction, microwave irradiation, ion exchange, and melting reaction. Due to the simplicity of its use, calcination is the most facile method in the chemical industry. In this work, the titanium precursor, TiO2, was used to synthesize PHT whiskers according to previously reported procedures, with some modifications [2]. An appropriate amount of TiO2 and anhydrous K2CO3 were milled and sifted through a 100-mesh sieve (150 μm pore size), respectively. TiO2 (79.86 g, 1.0 mol) and anhydrous K2CO3 (24.87 g, 0.18 mol) were mixed in a high-speed mixer for 3 min. The mixture was dried in an oven for 3 h at 150 °C, and then transferred to a Muffle furnace with a corundum crucible. The mixture was gradually heated to 1000 °C at a rate of 10 °C/min, and then kept for 1 h at 1000 °C. After it was naturally cooled to room temperature, the product was washed to pH = 7 and filtered. Finally, the solid product, designated PHT-1, was dried in an oven for 6 h at 150 °C.
In addition to the above procedure, two modifications of the preparation were also considered to compare. Case 1: PVP (1 g) was additionally added to the mixture in a high-speed mixer. The resulting product was denoted as PHT-2. Case 2: Both PVP (1 g) and water (200 mL) were added to the mixture. Instead of using a high-speed mixer, the mixture was ball-milled for 30 min. The water was then removed using a rotary evaporator. After the mixture was dried in an oven for 3 h at 150 °C, it was weighed. The corresponding product, denoted as PHT-3, was obtained by calcination at a high temperature according to the above procedure.

2.3. Surface Modification of PHT Whiskers

Here, PHT-1 was used as an example. A silane coupling agent (0.5 mL) was added to an ethanol solution (100 mL, 95%, v/v). It was mixed by ultrasound for 30 min. The prepared PHT-1 whiskers (10 g) were slowly added, and the mixture was gently stirred for 3 h at room temperature. After filtration, it was dried for 24 h at 150 °C, and then the surface-modified PHT whiskers were obtained. Note that they were denoted as PHT-1-1, PHT-1-2, or PHT-1-3 for PHT-1 modified with KH-550, KH-560, or KH-570.

2.4. Reinforcement of Polyethylene (PE)

PE resin (97 g) and modified PHT whiskers (3 g) were mixed with a powerful mixer (HSLX100, Shandong Hengshi Machinery Technology Co., Ltd., Jining, China) and then added to a twin-screw extruder (TDS-20, Zhangjiagang Friend Machinery Co., Ltd., Zhangjiagang, China). It was processed at a speed of 45 rpm/min, a pressure of 2.31 MPa at the head, a current of 0.3 A, an extrusion temperature of 210 °C, and a melt temperature of 237 °C. The extrudate was dried and cut into small particles for use as samples. The obtained samples of the composites were denoted as PE/PHT-1-1, PE/PHT-1-2, PE/PHT-1-3, etc.
The composite particles were subsequently molded into sheets using a sheet vulcanizing machine (XLB-50D/Q, Shanghai Shuangyi Rubber and Plastic Machinery Co., Ltd., Shanghai, China) at <180 °C. After the molded sheets were cooled in water for 2 h and then at room temperature for 48 h, their mechanical properties were tested using a universal material testing machine (SX-049, Shaanxi LESSO Technology Industrial Co., Ltd., Xianyang, China).

2.5. Characterization

The morphology and microstructure of the prepared whiskers were characterized by scanning probe microscopy (EIProcscan ELP3, HEKA Instruments Inc., Reutlingen, Germany) at 15 kV. X-ray diffraction (XRD) patterns were recorded at a rate of 0.05°/min with a Panalytical X’pert MRD diffractometer (Dutch Panaco Company, Zaandijk, The Netherlands) adopting Cu Kα radiation (λ = 0.15406 nm). The surface chemical properties of the samples were studied by X-ray photoelectron spectroscopy (XPS, Axis Ultra DLD, Kyoto, Japan). A monochromatic Al Kα X-ray was used to calibrate the electron binding energy at the C 1s spectral line (284.8 eV).

3. Results

3.1. Characterization of PHT Whiskers

3.1.1. Morphology Studies

The prepared PHT-1 and PHT-2 are white needle-like crystals in 73.4% and 79.2% yields, respectively, and PHT-3 is a gray needle-like crystal in a 68.3% yield. The SEM images of PHT-1, PHT-2, and PHT-3 are shown in Figure 2, Figure 3 and Figure 4, respectively. As shown in Figure 2a, a small agglomeration is found in the synthesized potassium hexatitanate whiskers (PHT-1). Figure 2d clearly shows that the crystal of PHT has a slender rod-like shape with smooth and flat surfaces in a good length-to-diameter ratio. Notably, as shown in Figure 3, the SEM images indicate, compared to PHT-1, that PHT-2 whiskers are better looking, with more whiskers in a high length-to-diameter ratio and which are more even. On the contrary, Figure 4 shows that PHT-3 whiskers have a higher agglomeration and are mostly short and coarse. In addition, the length-to-diameter ratio of PHT-3 is lower than that of PHT-1 or PHT-2. Therefore, PHT-2 whiskers would be more suitable for reinforcement. In this sense, it is very important to use the PVP additive in the synthesis to improve the quality of whiskers. We believe that PVP can be considered as a template to control the growth orientation of the crystal and shape its morphology.
As shown in Figure 5, all main peaks for the XRD patterns of PHT-2 are in good agreement with the reference from the database (ICSD No. 25712), which undoubtedly indicates that the prepared sample is K2Ti6O13.

3.1.2. XPS Analysis

As mentioned above, only PHT-2 whiskers are discussed here. The wide scanned XPS spectrum of PHT-2 is shown in Figure 6. It shows that the prepared material is composed of O, C, Ti, Na, and K elements. The corresponding contents are listed in Table 1. Note that the small amount of Na originates from the impurities of K2CO3. For each element, the corresponding XPS spectra are fitted to obtain more information about the valence state. As shown in Figure 6b, two peaks of K 2p at 291.4 and 294.2 eV would be attributed to 2p3/2 and 2p1/2 states of K+ in PHT, respectively. Figure 6c shows two states of Ti 2p, i.e., 2p1/2 and 2p3/2. The corresponding binding energies are 463.3 (Ti 2p1/2) and 457.6 eV (Ti 2p3/2), which are related with Ti4+ in the TiO6 octahedron of PHT. For the O atom, as shown in Figure 6d, the XPS peak can be fitted to two states. As shown in Figure 1, since not all O atoms are equivalent in PHT, the binding energies of 592.0 and 530.6 eV would be attributed to the O atoms in Ti-O-Ti and K-O-Ti, respectively.

3.2. Characterization of Surface-Modified PHT Whiskers

Three silane coupling agents (KH-550, KH-560, and KH-570) were used in this work. The proposed modification mechanism is shown in Scheme 1. The silane coupling agent undergoes hydrolysis and then condenses to oligomers via dehydration. Due to the active hydroxyl groups on the surface of PHT whiskers, the oligomers of coupling agents can easily bind with PHT whiskers via dehydration. In this way, the surfaces of PHT whiskers can be modified by a suitable coupling agent, reducing the surface energy and increasing the interaction in the composites [42].
Having a good length-to-diameter ratio, PHT-1 and PHT-2 were used for surface-modification in this work. Due to the excellent mechanical properties (see details in the following section), PHT-2 modified with KH-550 is taken as an example (PHT-2-1) to be discussed here. As shown in Figure 7, SEM images indicate that the whiskers have little change in shape after surface modification. The aggregate becomes weaker, and most of the whiskers also retain high length-to-diameter ratios, supported by the high-resolution images as shown in Figure S1 in the Supplementary Materials. On the other hand, it is observed that the surface becomes rough to a certain extent due to the attachment of coupling agents. As shown in Figure 8, the XRD patterns also indicate that the crystal structure of PHT does not change in the modified whiskers. Note that Figure S2 in the Supplementary Materials also shows similar results for PHT-1 composites. In fact, the silane coupling agents only have an influence on the surface, and there is no collapsing or cracking during the modification process. As shown in Figure 9 and Table 1, the wide scanning XPS spectrum and the content of elements show that the Si element is present in PHT-2-1, indicating that the KH-550 successfully binds to the surface of the whiskers. As shown in Figure 9d, only one peak was found, and the corresponding binding energy of Si is at 103.6 eV. It could be attributed to Si 2p of Si4+ in Si-O, instead of Si atom whose binding energy of 2p state is at around 99~100 eV. Thereby, no reduced Si is found in composites. Notably, in that the coupling agent covers the surface, only one peak of O 1s at 532.4 eV (Figure 9c) is found in XPS. This signal would originate from the silane coupling agent.

3.3. Mechanical Test

The pictures of small particles and molded sheets are shown in Figures S3 and S4 in the Supplementary Materials. Notably, there is no obvious difference in color or shape for these composites. The tensile strength, modulus of elasticity, shear strength, and shear elasticity are investigated using a universal material testing machine. Note that unfilled PE is taken as a blank. The results are shown in Table 2. Compared to unfilled PE, the mechanical properties of all composites are enhanced to some extent. The mechanical properties of composites based on PHT-2 are generally better than those based on PHT-1, consistent with the morphology discussed above. Among them, PE/PHT-2-1 shows the best morphology. The tensile strength and modulus of elasticity of PE/PHT-2-1 increase to 21.7 and 2017 MPa, respectively, which are higher than those of PE (18.3 and 1947 MPa). This means that the tensile strength and modulus of elasticity increase by 18.6% and 3.6%, respectively. In particular, the elongation at break for PE/PHT-2-1 increases dramatically to 38.1%, revealing that its softness and elasticity are significantly enhanced. For the shear properties, a slight improvement is found for PE/PHT-2-1. The corresponding shear strength and shear elasticity are 34.1 and 1910 MPa, slightly stronger than those of untreated PE (33.8 and 1900 MPa). Since the fraction of whiskers in a composite is small (ca. 3%, w/w), the density of mass for each composite is little changed. Overall, the small amount of surface-modified PHT whiskers can definitely reinforce PE and improve mechanical properties such as tensile and shear strength, resulting in better wear resistance.

4. Conclusions

The reinforcement of polyethylene with potassium hexatitanate whiskers was investigated in this work. Potassium hexatitanate whiskers were prepared through the calcination of TiO2 and K2CO3. The main research findings are as follows, highlighting that a small amount of potassium hexatitanate whiskers can effectively enhance the mechanical properties of polyethylene.
  • It was demonstrated that the PVP additive is highly effective in regulating the growth of crystals. The prepared potassium hexatitanate whiskers exhibit a slender, rod-like morphology with smooth and flat surfaces and a large length-to-diameter ratio.
  • After the surface modification with silane coupling agents (KH-550, KH-560, and KH-570), the whiskers showed little change in shape. The results of the mechanical tests indicate that there is some improvement in the tensile strength, the modulus of elasticity, the shear strength, and the shear elasticity.
  • Among the composites, the KH-550 modified composite (PE/PHT-2-1) exhibits the best performance. An increase of 18.6% in the tensile strength and 3.6% in the modulus of elasticity are observed. The modified PE composite shows enhanced softness and elasticity. The elongation at the break for PE/PHT-2-1 increases significantly to 38.1%.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/jcs9010011/s1, Figure S1: SEM images of the prepared PHT-2-1, PHT-2-2, and PHT-2-3 samples; Figure S2: XRD patterns of the prepared PHT-1-1, PHT-1-2, and PHT-1-3 composites; Figure S3: Small particles of composites; Figure S4: Molded sheets of composites.

Author Contributions

Methodology, Software, Investigation, Writing—original draft, Writing—review and editing, Q.P.; Conceptualization, Methodology, Supervision, Writing—review and editing, Q.J.; Investigation, J.X.; Formal analysis, Project administration, X.L.; Supervision, Conceptualization, Writing—review and editing, Y.W.; Conceptualization, Funding acquisition, Y.S.; Conceptualization, Resources, Writing—review and editing, S.C. and B.Y.; Formal analysis, Writing—review and editing, Z.C. and K.P. All authors have read and agreed to the published version of the manuscript.

Funding

Qin-Xiang Jia acknowledges financial support from Natural Science Foundation of Shaanxi Province, China (Grant No. 2023-JC-YB-125).

Data Availability Statement

The original contributions presented in the study are included in the article; further inquiries can be directed to the corresponding authors.

Conflicts of Interest

Q.P., X.L., and Y.S. were employed by Xingyi Advanced Materials Technology Co., Ltd. S.C. and B.Y. were employed by Shaanxi LESSO Technology Industrial Co., Ltd., Xianyang, China. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

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Figure 1. Crystal structure of K2Ti6O13 [3]. Space group: C2/m; cell parameters: a = 15.582 Å, b = 3.820 Å, c = 9.112 Å, α = γ = 90°, β = 99.764°. The purple balls are K atoms, the red balls are O atoms, and each octahedral structure is a unit of TiO6.
Figure 1. Crystal structure of K2Ti6O13 [3]. Space group: C2/m; cell parameters: a = 15.582 Å, b = 3.820 Å, c = 9.112 Å, α = γ = 90°, β = 99.764°. The purple balls are K atoms, the red balls are O atoms, and each octahedral structure is a unit of TiO6.
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Figure 2. SEM images (a–d) of PHT-1 sample.
Figure 2. SEM images (a–d) of PHT-1 sample.
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Figure 3. SEM images (a–d) of PHT-2 sample.
Figure 3. SEM images (a–d) of PHT-2 sample.
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Figure 4. SEM images (a–d) of PHT-3 sample.
Figure 4. SEM images (a–d) of PHT-3 sample.
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Figure 5. XRD patterns of (a) the as-prepared PHT-2 sample and (b) K2Ti6O13 from the database (ICSD No. 25712).
Figure 5. XRD patterns of (a) the as-prepared PHT-2 sample and (b) K2Ti6O13 from the database (ICSD No. 25712).
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Figure 6. XPS spectra of PHT-2 sample. (a) Wide spectrum; (b) K 2p; (c) Ti 2p; (d) O 1s.
Figure 6. XPS spectra of PHT-2 sample. (a) Wide spectrum; (b) K 2p; (c) Ti 2p; (d) O 1s.
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Scheme 1. The proposed modification mechanism for potassium titanate whiskers (PTWs) using a silane coupling agent.
Scheme 1. The proposed modification mechanism for potassium titanate whiskers (PTWs) using a silane coupling agent.
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Figure 7. SEM images (a,b) of the prepared PHT-2-1 sample.
Figure 7. SEM images (a,b) of the prepared PHT-2-1 sample.
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Figure 8. XRD patterns of the prepared PHT-2-1, PHT-2-2, and PHT-2-3.
Figure 8. XRD patterns of the prepared PHT-2-1, PHT-2-2, and PHT-2-3.
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Figure 9. XPS spectra of PHT-2-1 sample; (a) Wide spectrum; (b) C 1s; (c) O 1s; (d) Si 2p.
Figure 9. XPS spectra of PHT-2-1 sample; (a) Wide spectrum; (b) C 1s; (c) O 1s; (d) Si 2p.
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Table 1. Lookup binding energies (Eb, eV) and contents (Percentage, %) of elements in PHT-2, PHT-2-1, and PHT-1-1.
Table 1. Lookup binding energies (Eb, eV) and contents (Percentage, %) of elements in PHT-2, PHT-2-1, and PHT-1-1.
O(1s)C(1s)Ti(2p)Na(1s)K(2p)Si(2p)
528.8290.8456.81066.8290.8100.8
PHT-226.4451.768.340.4213.04-
PHT-2-127.4949.206.810.6012.393.51
PHT-1-126.8050.137.590.2412.632.62
Table 2. Mechanical properties of the PE/PHT composites.
Table 2. Mechanical properties of the PE/PHT composites.
SamplesTensile Strength (MPa)Elongation at Break (%)Modulus of Elasticity (MPa)Shear Strength (MPa)Shear Elasticity (MPa)Density
(kg/m3)
PE18.36.84194733.819001204
PE/PHT-1-118.844.7181030.717401242
PE/PHT-1-217.19.02183029.718001232
PE/PHT-1-319.539.1174031.212081229
PE/PHT-2-121.738.1201734.119101218
PE/PHT-2-219.719.7197032.819701232
PE/PHT-2-221.236.4195034.015301222
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MDPI and ACS Style

Pan, Q.; Jia, Q.; Xie, J.; Li, X.; Wu, Y.; Sun, Y.; Chu, S.; Yang, B.; Chen, Z.; Peng, K. Reinforcement of Polyethylene with Potassium Hexatitanate Whiskers: Importance of Polyvinylpyrrolidone Additive. J. Compos. Sci. 2025, 9, 11. https://doi.org/10.3390/jcs9010011

AMA Style

Pan Q, Jia Q, Xie J, Li X, Wu Y, Sun Y, Chu S, Yang B, Chen Z, Peng K. Reinforcement of Polyethylene with Potassium Hexatitanate Whiskers: Importance of Polyvinylpyrrolidone Additive. Journal of Composites Science. 2025; 9(1):11. https://doi.org/10.3390/jcs9010011

Chicago/Turabian Style

Pan, Qin, Qinxiang Jia, Jin Xie, Xiaoyong Li, Yong Wu, Yang Sun, Suihong Chu, Bo Yang, Zhexi Chen, and Kewei Peng. 2025. "Reinforcement of Polyethylene with Potassium Hexatitanate Whiskers: Importance of Polyvinylpyrrolidone Additive" Journal of Composites Science 9, no. 1: 11. https://doi.org/10.3390/jcs9010011

APA Style

Pan, Q., Jia, Q., Xie, J., Li, X., Wu, Y., Sun, Y., Chu, S., Yang, B., Chen, Z., & Peng, K. (2025). Reinforcement of Polyethylene with Potassium Hexatitanate Whiskers: Importance of Polyvinylpyrrolidone Additive. Journal of Composites Science, 9(1), 11. https://doi.org/10.3390/jcs9010011

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