Advanced Industrial and Engineering Polymer Research最新文献

Polymer blends are mixtures of two or more macromolecular species – polymers and/or copolymers. They are used to increase the range of properties available from existing polymers without synthesizing new ones, which is time consuming and expensive. But most blends are immiscible, and need to be compatibilized. The compatibilization must not only insure improvement in performance, it must be clearly defined with regard to the method and objective. Keeping this view in focus, the present review classifies the main approaches that are available into four well-defined “routes” to compatibilization for various types of polymers and copolymers. Further, the possibility of using an innovative combination of in-situ polymerization and in-situ compatibilization as a new route to polymeric nano-blends is explained. While most of the present narrative deals with different types of binary polymer/copolymer blends, pathways for extension of some of the methods to ternary or multicomponent blending and the significance of the novel composite compatibilizers in this context are also highlighted.

Recent developments in nanomaterials have come to extensive use in various fields, especially in the biomedical industry. Numerous significant obstacles still need to be overcome, particularly those about utilizing nanomaterials in biomedical science, before they can be used for medicinal purposes. Major issues in biomedicine include biological functioning, harmony, toxic effects, and nano-bio surface properties. Thus, researchers may use cutting-edge characterization approaches to study nanomaterials for biomedical applications. Two-dimensional nanomaterials and polymers are crucial components of biological systems. Polymer-based nanomaterials are flexible and more resistant to chemical attack than other NPs. Polymers easily form composite or functionalization with other NPs to improve their performance compared to the traditional NPs. The current review article discussed nanomaterial performance, including carbon nanotubes (CNTs), graphene, MXene and polymers-based biomedical applications. The current state of nanomaterials in the biomedical area is illustrated in this summary article, along with applications and the significance of characterization approaches. The advanced methods for examining the interior geometry, structure, and morphology of nanomaterials are discussed in this piece of writing, including Transmission electron microscopy (TEM), Scanning electronic microscopy (SEM), Atomic Force Microscopy (AFM), Magnetic resonance force microscopy (MRFM) and X-ray diffraction (XRD). Finally, the authors discussed the issues associated with nanomaterials in biomedical applications.

Aim

To evaluate the in vivo toxicity of the anionic nanoliposome formulation containing [hydrogenated soy phosphatidylcholine (HSPC)] and [1,2-distearoyl-sn-glycero-3- phosphoglycerol (DSPG)].

Methods

The anionic nanoliposome formulation was prepared by the lipid film hydration method. To assess the toxicity of anionic nanoliposomes, male and female albino mice were weakly treated with intravenous injection of the formulation (100 μmol/kg) for four weeks. The toxicity study was performed by the subacute protocol, four weeks after the last injection. To this end, the plasma levels of lipid indexes, urea, creatinine, AST, ALT, ALP, and fasting blood glucose (FBG) were measured. To evaluate histopathological alterations, the tissues of the vital organs including the heart, liver, kidneys, spleen, and brain were studied using hematoxylin & eosin (H&E) staining.

Results

The results showed nonsignificant changes in total cholesterol, LDL-C, HDL-C, creatinine, urea, AST, ALP, and ALT in the liposome-treated mice when compared with control mice. However, plasma levels of triglycerides were significantly decreased (by 64.5 ± 15.3 mg/dL, p = 0.001) and (by 58.75 ± 15.3 mg/dL, p = 0.002) in the liposome-treated male and female mice, respectively, when compared with corresponding control mice. The FBG level was significantly increased by154 ± 20 mg/dL, p = 0.001 in the liposome-treated male mice when compared with the control male mice. The PAB level was significantly decreased by 12 ± 4.2 HK, p = 0.03 in the liposome-treated male mice when compared with the control male mice. Histological examination of vital organs indicated no significant differences in tissue damage between the liposome-treated and control mice.

Conclusion

The findings of the present study indicated that DSPG-containing nanoliposome formulation exerted no significant adverse effects on the function of vital organs and blood levels of biochemical biomarkers in healthy mice. However, further investigations are needed to find a safe dose of DSPG liposomes concerning the risk of diabetes.

The study of nanocomposite hydrogels in their various scientific areas has grown remarkably along the years with emergence of various theoretical and experimental techniques. Therefore, this review is categorized to provide a comprehensive guide on the fabrication of nanocomposite hydrogels. In this regard, the type and amounts of nanomaterial, and the hydrogel network formation have a significant impact on the improvement of physical, chemical, and biological properties of hydrogels. It has to be noted that these parameters are dependent on the application of nanocomposite hydrogels.

Therefore, the orientation of the range of nanomaterials, product characteristics, along with sufficient information on the application of these materials, need to be considered to obtain a successful material.

In this review article, the scientific advances in the field of nanocomposite hydrogels, focusing on their types based on the nanoparticle types, and their properties with a new perspective on rheology, self-healing behavior, thermal stability, biologic, and morphology are investigated. Eventually, the applicability of these materials is collected in a comprehensive table in various fields such as biomedical, enhanced oil recovery, agriculture, etc. for the first time presents comparisons with more details.

Additive Manufacturing (AM) has been a noticeable technology and made significant progress since the late 1980s. Despite the tremendous growth, this technology is still facing numerous manufacturing challenges. AM of structures and smart materials such as shape memory polymers and alloys is one of the most actively researched areas in which printed objects can alter their properties and shape when exposed to a stimulus e.g., light, temperature, magnetic fields, pH, and humidity. The AM-build parts which can take advantage of these shape-changing features, lead to the growth of 4D printing by introducing time as a fourth dimension in AM processes. This new field originated in 2013, and since then, it has generated great interest due to its potential to build innovative, multi-functional, self-assembling, and self-repairing components with modifiable properties, shapes, and functionalities. This review article intends to examine the major developments of 4D printing in the biomedical field. The study will provide an overview of various 4D printing technologies including vat photo-polymerization, extrusion-based methods, and material jetting and their uses in the biomedical field. It focuses on smart materials like SMPs, LCEs, SMPAs, etc., and their applications in various industries e.g., mechanical, biomedical, aerospace, etc., and explores external stimuli such as moisture, temperature, pH, magnetic fields, and light. The article delves into the promising applications of 4D printing in biomedical fields such as drug delivery, orthopedics, medical devices, tissue engineering, and dentistry and analyzes the challenges associated with 4D printing in the biomedical field, and suggests the future directions including optimization of printing parameters, and exploration of novel materials to broaden its applications.

Bacterial nanocellulose (BNC), as a natural polymer, produced in vivo by bacteria and in vitro by the cell-free enzymes system, is comprised of nano-sized fibers. The pristine BNC possesses unique structural, physiological, and biological properties. Its fibrous and porous morphology allows the incorporation of natural and synthetic polymers, nanomaterials, clays, etc., while the presence of free hydroxyl (OH) groups allows its chemical modification with a variety of functional groups to form nanohybrids. These hybrids not only have superior properties to those of pristine BNC but possess additional functionalities imparted by the reinforcement materials. The properties of BNC-based nanohybrids can be tuned at macro, micro, and nano-scales as well as controlled at molecular levels. This review consolidates the current knowledge on the synthesis of β-(1,4)-glucan chains, their excretion and organization into high-ordered nano-sized fibers, as well as functionalization, both at physiological and molecular levels. It comparatively discusses the microbial and cell-free synthesis of cellulose and discusses the potential merits and limitations of each method. It further explores the methods used for developing BNC-based hybrids and discusses the synthesis-structure-properties relationship of BNC-based hybrids to justify their use for targeted biotechnological applications. A large portion of this review is devoted to discussing the recent trends in the preparation of BNC-based nanohybrids for their biotechnological applications, including biomedical (i.e., wound healing, cardiovascular devices, neural tissues, bone and cartilage tissues, dental implants, and drug delivery) and non-biomedical (biosensing, cosmetics, food, bio- and optoelectronics, environment, energy, and additive manufacturing). Finally, it provides an outlook on the future BNC research for human welfare.

Graphene has unusual physical properties such as high thermal and electrical conductivity, high elasticity, and unique optical properties, making it suitable for a variety of biomedical applications in biosensing and drug delivery. Nanostructures of graphene and graphene derivatives have been fabricated and applied to different types of biosensors. In this article, we have reviewed recent advances in the fabrication of graphene-and graphene-derivatives-based nanomaterials, with a particular focus on green processes for producing bio-based graphene nanostructures. The various methods used to synthesize a few layers of graphene sheets, including the top-down and bottom-up approaches, have been thoroughly discussed. The benefits of using those green processes and current challenges are analyzed. We also discussed the applications of these nanomaterials in biomedical sensors. Current reviews for graphene-based nanostructures in biomedical sensors provide brief summaries of current technologies. We have reviewed current state-of-the-art graphene-based biosensors and provided an in-depth summary of their working mechanism and use of graphene nanomaterials to enhance their sensitivities. We have grouped these sensors based on their working principles, such as optical and electrochemical sensors for detecting and quantifying a variety of biomolecules and cells. The performance of the graphene nanomaterial-based biosensors have been compared with conventional biosensing techniques, and their pros and cons are discussed. We concluded the article by summarizing our findings, discussing current challenges, and outlining the future directions of using graphene-based nanostructures for biosensing applications.

Chitosan is obtained from chitin, which is abundantly found in crustaceans and obtained through various methods. The demineralization, deproteinization, discoloration, and deacetylation of chitin produce chitosan consisting of d-glucosamine and N-acetyl d-glucosamine units that are linked through β-(1,4)-glycosidic linkages. Chitosan has gained significant attention in the biomedical field due to its unique properties such as abundance, renewability, non-toxic nature, antimicrobial activity, biodegradability, and polyfunctionality. One of its key properties is its antimicrobial activity, which is why it has been heavily utilized in the biomedical field. To provide a comprehensive overview of chitosan, this review discusses its extraction from chitin and its properties based on its source and extraction methods. It also delves into various chemical modifications and nanocomposite development using natural and synthetic materials. The review emphasizes the multitude of properties that make chitosan an excellent choice for a wide range of biomedical applications. It discusses various mechanisms of antibacterial activity and the factors affecting this activity. Additionally, the review highlights biodegradability, hemocompatibility, antioxidant activity, anti-inflammation, and other properties of chitosan that contribute to its suitability for different biomedical applications, including wound dressing materials, drug delivery carriers, biosensing and diagnostic devices, bone substitutes, and bioimaging. While discussing some limitations of chitosan, the review concludes with an overview of the future perspective for developing multifunctional chitosan-based nanomaterials that could potentially move from laboratory to clinical trials for treating various diseases.

Recent advancements in nanostructured materials have found widespread application across many domains, particularly in the biomedical field. Before using nanostructured materials in clinical applications, many important challenges, especially those related to their uses in biomedicine, must be resolved. Biological activity, compatibility, toxicity, and nano-bio interfacial characteristics are some of the major problems in biomedicine. We may therefore investigate the nanostructured materials for biomedical applications with the aid of modern characterization techniques. This overview article illustrates the present state of nanostructured materials in the biomedical field with uses and the importance of characterization methods through the use of cutting-edge characterization techniques. In this article, the techniques for analysing the topology of nanostructures, including Field Emission Scanning Electron Microscopy (FESEM), Dynamic Light Scattering (DLS), Scanning Probe Microscopy (SPM), Near-field Scanning Optical Microscopy (NSOM), and Confocal microscopy, are described. In addition, the internal structural investigation techniques X-ray diffraction (XRD), Transmission Electron Microscopy (TEM), and Magnetic Resonance Force Microscopy (MRFM) are discussed. In addition, composition analysis techniques such as X-ray Photoelectron Spectroscopy (XPS), Energy Dispersive X-ray spectroscopy (EDS), Auger Electron Spectroscopy (AES), and Secondary Ion Mass Spectroscopy (SIMS) have been discussed. The essence of the nanomaterials as they relate to physics, chemistry, and biology is thoroughly explained in this overview along with characterization techniques through case studies. Additionally, the constraints and difficulties with specimen and analysis that are related to comprehending nanostructured materials have been identified and addressed in this study.

Injection moulded specimens were produced from biodegradable poly(butylene succinate) (PBS)/organomodified montmorillonite (OMMT) nanocomposites, after melt compounding in different compositions. WAXD studies demonstrated that the OMMT formed similar intercalation levels in the 2.5–10 w/w% additive ratio range. It was also proved by rotational rheometry that the nanoclay stacks form physical network above 5 w/w% concentration, which significantly influence the viscoelastic properties of the melt. The value of zero shear viscosity also changed accordingly, starting to increase above 5 w/w% nanoclay content. The OMMT content reduced the creep sensitivity measured in molten state.

X-ray and DSC investigations showed that OMMT inhibits the crystallisation of PBS, resulting in a decrease in crystallinity at higher nanoclay ratios. As a result, the room temperature creep increased with the OMMT ratio.

The Young's modulus linearly increases in the entire concentration range exceeding 1.2 GPa at 10 w/w% nanoclay content. The value of yield strength does not change significantly (35–40 MPa), but the strain at yield – which characterises stiffness – and the notched Izod impact strength already decrease at 2.5 w/w% OMMT content, but further increasing the nanoclay content has minor effect. However, the nanocomposite with 10 w/w% OMMT can be a real alternative to polypropylene (PP) and high-density polyethylene (HDPE) injection moulded products based on its mechanical properties.

To characterise the effect of OMMT on dynamic mechanical properties, the S (Stiffening effectiveness), L (Loss effectiveness) and D (Damping effectiveness) indices were introduced to quantitatively describe the nanoclay effect intensity in each temperature range.