ENVIRONMENTAL POLLUTION
·
2022
·
IF 9.988
Fengjie Li,Xue Zhai,Mingxuan Yao,Xue Bai
Photoaging is an important reaction for waste plastics in the aquatic environment and plays a key role in the lifetime of plastics. Nevertheless, when natural photosensitive substances such as nitrate participate in this process, the physiochemical changes in plastics and the corresponding reaction mechanisms are not well-understood. In this work, the photochemical behavior of polyethylene terephthalate (PET) bottles in deionized water and nitrate solution was systematically investigated under ultraviolet (UV) irradiation. The analyses of the surface physicochemical properties of the photoaged PET bottles indicated that, after 20 days of photo-irradiation, the presence of nitrate reduced the contact angle from 69.8 ± 0.9° to 60.0 ± 0.3°, and increased the O/C ratio from 0.23 to 0.32, respectively. The leaching rate of dissolved organic carbon (DOC), which was 0.0193 mg g −1 ·day −1 in nitrate solution, was twice that of 0.00941 mg g −1 ·day −1 in deionized water. Furthermore, fluorescence spectroscopy revealed that the increasing DOC had aromatic rings with hydroxyl on the side-chain formed after UV irradiation. The positive effect of nitrate on the degradation of PET bottles was mainly through the generation of hydroxyl radicals that were produced through the photolysis of nitrate. In addition, two-dimensional correlation spectroscopy analysis showed that the chain scission of PET plastics could be initiated by nitrate-induced ·OH attacking the carbon-oxygen bonds instead of forming peroxides with oxygen. This work elucidates the mechanism of photodegradation of plastics that was induced by nitrate and highlights the important role of natural photosensitive substances in the photoaging process of plastics.
研究领域:
环境科学
·
材料科学
·
化学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Xuan Zhou,Wudi Zhang,Shuqiang Peng,Zhixuan Zhao,Wenxin Chen,Xiaohong Ding,Lixin Wu,Zixiang Weng
The chemical inertness of poly(ethylene terephthalate) (PET) fabrics poses challenges in achieving superhydrophobic coatings with durable adhesion on their surfaces. Conventional surface modification methods such as alkali etching and plasma etching typically compromise the favorable mechanical properties of PET. In this study, polydopamine (PDA) was utilized to functionalize the PET fabric nondestructively by creating robust and reactive hydroxyl and amine groups on its surface, which were subsequently used as a binder of superhydrophobic modifiers such as fluorine-free octadecyltrichlorosilane (OTS). By utilizing PDA to provide reactive groups, OTS undergoes self-assembly through hydrolysis on the surface of the PET fabric without introducing any inorganic nanoparticles while simultaneously forming low surface energy, strong covalent bonds, and rough surfaces. This robust material system provides a novel strategy to design and prepare superhydrophobic PET fabrics that can withstand extreme conditions and maintain superb water repellency even after 1000 times of abrasion and 100 washing cycles. Additionally, the room-temperature self-assembly properties of OTS provide the modified PET fabrics with efficient and repeatable room-temperature self-healing capability. This entire process through an environmentally friendly two-step immersion method enables large-scale production of superhydrophobic PET fabrics with wide applications in sports shoes and clothing.
研究领域:
材料科学
·
纺织工程
·
表面化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Autex Research Journal
·
2024
·Vol. 24
·期 1
·
IF 1.1
Sihui Pan,Hongfei Qian
In this study, ultrasound energy was applied to assist the alkali hydrolysis of polyethylene terephthalate (PET) fabric, and then, the results were compared with those of the mechanical oscillating method, which was used as the control. The effects of various factors such as the sodium hydroxide concentration, the dosage of dodecyl dimethyl benzyl ammonium chloride (DDBAC), and the frequency on the weight loss of the PET fabrics were systematically investigated. The surface appearance and microstructures of the treated fibers with different methods were analyzed using a scanning electron microscope and X-ray diffraction, respectively. The results showed that DDBAC played a prominent accelerating role in the hydrolysis of the PET polymer, and the frequency had a great influence on the weight loss of the PET fabric. Ultrasound with a frequency of 60 kHz showed a similar decomposition rate as the control, resulting in similar weight loss, which was the highest value among the three frequencies (20, 60, and 80 kHz). In addition, the application of ultrasonic energy led to more pits on the fiber surface, a smaller average grain size, and decreased crystallinity of the treated fibers, while the mechanical oscillating method resulted in slightly increased crystallinity. By comparing the K/S value of the dyed fabrics with two commercial disperse dyes, we found that the treatment method had no obvious correlation with the color depth of the treated fabric.
研究领域:
材料科学
·
纺织工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2024
·Vol. 141
·期 42
·e56117
·
IF 2.7
Mengxia Xu,Jingshun Liao,Zhu Luo,Ruhui He,Shenglong Yang,Hai Li,Yehan Yang
Polypropylene double-grafted maleic anhydride and bisphenol A epoxy resin (PP-g-M-E) was successfully prepared by a single-step method and characterized by Fourier-transform infrared spectroscopy. Subsequently, it was employed as a compatibilizer to fabricate polypropylene (PP)/polyethylene terephthalate (PET) blends via melt extrusion. The content of the PET dispersed phase in the composite varied from 0 to 30 phr. The microstructure and morphology of the composites were characterized using scanning electron microscopy and Raman spectroscopy. The addition of PP-g-M-E increased the interfacial interaction between the two phases and improved the compatibility and thermal stability of the system. In the presence of the compatibilizer, the crystallinity of the matrix phase (PP) increased, while that of the dispersed phase (PET) decreased owing to the heterogeneous nucleation effect of uniformly distributed PET. Double grafting of the PP-g-M-E compatibilizer considerably enhanced the mechanical performance of the PP/PET blend system. The elongation at break of the modified sample exceeded that of the PP/PET blends by 117.55%, and the flexural and impact properties also showed considerable improvement.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL RESEARCH
·
2025
·
IF 7.7
Hao Xing,Ekram Akram,Rohan Ali,Yunzhengshan Gao,Yifei Zhang
Enzymatic PET degradation presents a sustainable and eco-friendly solution for recycling and upgrading PET materials. While various PET-degrading enzymes have proven effective in converting low-crystallinity PET into monomers, their efficiency decreases significantly for high-crystallinity PET. Given that most commercially available PET products are highly crystalline and have a limited specific surface area, conventional methods typically resort to heat treatment and ball milling to achieve decrystallization and micronization before enzymatic hydrolysis. However, these pretreatments often compromise environmental benefits due to their high energy consumption and dust pollution, and are difficult to scale up. In this study, we developed a chemoenzymatic strategy that efficiently depolymerizes waste PET materials into monomers in just 4 hours. This process involves an alkaline treatment with diluted NaOH in 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP), followed by enzymatic hydrolysis of the PET nanosuspensions generated from solvent exchange. The alkaline treatment partially breaks down the PET molecular chains and mitigates recrystallization during the precipitation process. Importantly, the complete hydrolysis of PET is attributed to reduced crystallinity rather than particle size. Notably, this method eliminates the need for PET micronization and minimizes the usage of NaOH. The effectiveness of this method was demonstrated through the hydrolysis of various commercially available PET products, showcasing its potential to advance enzymatic degradation processes for PET recycling.
研究领域:
环境科学
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Polymer Chemistry
·
2025
·Vol. 16
·期 10
·1197-1207
·
IF 3.9
Jia-Ming Song,Xue-Shuai Wang,Jun-Yu Li,Yi Liu,Liu-Chun Zheng
The functionalization of poly(ethylene terephthalate) (PET) can potentially expand the applications of PET, particularly in high-value-added fields. To address the limitations of the low ionic content of traditional anionic PET, our study employs sodium dimethyl isophthalate-5-sulfonate (SIPM) as the ionic monomer. The copolymer was synthesized by transesterification and polycondensation. Ethylene glycol (EG) or butanediol (BDO) was applied to react with SIPM to obtain different types of ionic SIPE or SIPB. The ionic monomers are introduced into the PET macromolecular chains by reacting dimethyl terephthalate (DMT) and EG with SIPE or SIPB; for the first time, the effect of ion types and contents on PET properties was systematically studied. The incorporation of ionic groups leads to a notable enhancement in the mechanical, thermal, and hydrophilic properties of PET ionomers. The introduction of SIPB effectively improves the elongation at break and impact strength of PET, while the incorporation of SIPE substantially enhances the tensile and flexural strength of PET. Furthermore, an increase in the ion content evidently improves the hydrophilicity of the PET ionomer, with maximum water absorption of 30% and lowest water contact angle of 67°. With the introduction of the ion group, the macromolecular chain's regularity was disrupted, and the crystallinity of the PET ionomers was reduced. These changes promise an increase in transparency. Consequently, PET exhibits great potential to be applied in packaging materials, the textile industry, and the optical field.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS LETTERS
·
2016
·Vol. 147
·期 1
·240-252
·
IF 2.294
Suo Qianqian,Zi Jiangzhi,Bai Zilong,Qi Shoushan
Abstract Three metal organic framework catalysts (ZIF-8, ZIF-67, MOF-5) were prepared and used in the glycolysis of poly(ethylene terephthalate) (PET). All catalysts showed excellent catalytic activities, especially ZIF-8. The raw material ratio in ZIF-8 catalysts was optimized. The effects of reaction conditions on the conversion of PET and yield of bis(hydroxyethyl) terephthalate (BHET) were examined. Graphical Abstract In the presence of ZIF-8, the PET pellets can be fully degraded within 1.5 h at 197 o C, and the main product and by-products were proved to be BHET monomer and its dimers, respectively.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE AMERICAN OIL CHEMISTS SOCIETY
·
2021
·Vol. 98
·期 6
·673-682
·
IF 1.849
Changqing Miao,Yanbo Wang,Zhiying Ma,Yang Luo,Yu Miao,Pingfang Yuan,Jiao Guo,Gairong Chen,Hongbo Liu
In this study, poly( p- phenylenediamine) (PPDA) was synthesized by an enzymatic polymerization method using p- phenylenediamine as the monomer in the water phase. The PPDA structure was characterized by infrared (IR), gel permeation chromatography, and elemental analysis. The antioxidation behavior of the as-synthesized PPDA in biodegradable castor oil was investigated using a rotary oxygen bomb test and pressurized differential scanning calorimetry. A theoretical calculation was conducted to investigate its antioxidation mechanism. PPDA was found to exhibit excellent oxidation resistance in castor oil at 150 °C, which effectively prolonged the oxidation induction time of the oil. The results obtained herein suggest that as with phenolic antioxidants, PPDA with a hindered structure effectively improves the antioxidation performance of the oil by enhancing the stability of nitrogen free radicals.
研究领域:
材料科学
·
生物化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Nano Materials
·
2021
·
IF 5.097
Wenguang Yu,Xuefeng Gao,Haihui Liu,Xuechen Wang,Xingxiang Zhang
Nanocomposite materials with carbon nanotubes and graphene additives have long been considered to be exciting prospective nanomaterials for nanotechnology applications. Some issues of these nanomaterials include poor load transfer, poor interfacial engineering, poor dispersion, and viscosity-related issues, which lead to processing challenges in such nanocomposites, however. Both hydroxylated graphene oxide (GO-OH) and polyketone (PK)-functionalized graphene oxide (GO-PK) were used to improve the properties of polyethylene terephthalate (PET)/PK/graphene oxide (GO) composite fibers. The results showed that there were multiple interactions in the GO-PK. At the molecular level, interactions between PET and PK with GO-PK enhanced their miscibility, and thus, a stable fibril phase structure could be produced following the phase separation. These interactions were demonstrated by various characterization methods. When the fiber with 15 wt % PK/0.1 wt % GO-PK was subjected to 60 min of ultraviolet (UV) treatment, the tensile strength and Young’s modulus increased by 37.1 and 77.2% compared with those of 15 wt % PK fibers. This indicated that functionalized graphene oxide has excellent development potential for high-performance nanocomposite fibers.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
MACROMOLECULES
·
2023
·
IF 5.5
Peng Zhang,Lin Chen,Yan Guo,Lei Zhang,Xiu-Li Wang,Yu-Zhong Wang
Inspired by the interpenetrating network of nature leaf-vein, non-composite polymer materials with ultra-robust, lightweight, and fully recyclable properties are synthesized by a “hetero-furan unit”-driven multiscale design. That is, starting from the primary chemical structure at the molecular scale, the furan group is copolymerized in a polymer chain (polyethylene terephthalate, PET). Then, these “hetero-furan units” simultaneously regulate the secondary chain conformation (nano-scale) and the tertiary aggregate structure (micro-scale) of the PET copolymer, thereby driving the spontaneous growth of the “leaf-vein”-mimicking crystal reinforcement phase. Requiring only less than 1% furan units, corresponding copolymer PET-FN1 not only exhibits surprising fourfold increase in toughness (tensile toughness of 346 MJ m–3 and impact strength of 69.8 kJ m–2) and 40% increase in tensile strength (83.6 MPa) but also achieves lower density and easy processing. This demonstrates the super-efficiency of this bioinspired multiscale design regulated by the original chemical structure. Especially, copolymer PET-FN1 can be quickly chemically recovered under mild conditions (80 °C, 4 h) to obtain raw monomers with a purity of 99.8%. This work opens up a new perspective for developing advanced polymer materials with excellent mechanical properties, lightweight, and environmentally friendly recycling, which will greatly benefit the global circular economy and sustainable development.
研究领域:
材料科学
·
仿生学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
POLYMER
·
2023
·
IF 4.6
Zhenhui Bai,ZhengQi Wang,Jie Jia,Dequn Wu,Xueli Wang,Jianyong Yu,Ruchao Yuan,Faxue Li
The charring enhancement of polymers at high temperatures is essential for improving their anti-dripping, flame inhibition and smoke suppression performance. In this work, a highly thermostable and charring phosphorus-nitrogen (P/N)-based flame retardant (HMCP), which can boost the char-forming of poly(ethylene terephthalate) (PET) was synthesized. Amazingly, melt-dripping of PET was completely suppressed as 4 wt% of HMCP was added. For PET composite with 8 wt% of HMCP (PET/HMCP8), its limiting oxygen index increased to 33.6% and the flame self-extinguished within 5 s. Besides, the after-flame time and total smoke production of PET/HMCP8 were reduced by 96.1% and 39.5% respectively compared with pure PET. The enhanced fire safety of PET/HMCP composites was attributed to the barrier effect and the dilution effect produced by the synergism of P/N-based heterocycle and benzimidazole groups. Additionally, PET fabric woven with the filaments prepared by the melt spinning of PET/HBCP4 presented pleasing fire safety and mechanical properties .
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2023
·
IF 5.2
Xiaowei Yang,Ying Wang,Qian Huang,Yuqing Zeng,Wangyang Lu,Xianan Qin
Polyethylene terephthalate (PET) can prevent bacteria from adhesion by repelling the bacteria with its negatively charged surface. However, it is commonly believed that it does not have the ability to directly inactivate bacteria. Surprisingly, we have found that alkali-treated PET nanofibers , which are also negatively charged due to the carboxyl end groups, can have remarkable antibacterial properties (antibacterial rate (AR) at 89% and 75%, against S.aureus and E.coli , respectively). We find that alkali-treatment has brought increased carboxyl end groups to the surface, making the surface more negatively charged. The positively charged cetyltrimethylammonium ions (CTA + ) that are used as catalysts for the alkali-treatment can form stable electrical double layers (EDL) with the carboxyl groups near the fiber surfaces, and the enriched CTA + in EDL can efficiently inactivate the bacteria. Based on these, an effective heavy-metal free antibacterial fiber has been developed by loading iron-phthalocyanine to the nanofibers. This phthalocyanine-empowered antibacterial fiber can inactivate bacteria under dark conditions (99% AR) by the surface CTA + and the generated weak reactive oxygen species .
研究领域:
材料科学
·
生物学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）