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Topic Review
Alginate Microparticles for Food, Pharmaceutical and Cosmetic Applications
Alginates are the most widely used natural polymers in the pharmaceutical, food and cosmetic industries. Usually, they are applied as a thickening, gel-forming and stabilizing agent. Moreover, the alginate-based formulations such as matrices, membranes, nanospheres or microcapsules are often used as delivery systems. Alginate microparticles (AMP) are biocompatible, biodegradable and nontoxic carriers, applied to encapsulate hydrophilic active substances, including probiotics.
  • 815
  • 21 Oct 2022
Topic Review
Polypropylene Extrusion Molding Production Quality
Polypropylene is derived from the reaction of petrochemical propylene gas with a density of 0.89–0.94 g/cm3. It is a lightweight plastic material with a semitransparent white color and has a lower cost than other plastic materials.
  • 807
  • 02 Jun 2022
Topic Review
Polyurea for Blast and Impact Protection
Polyurea has attracted extensive attention from researchers and engineers in the field of blast and impact protection due to its excellent quasi-static mechanical properties and dynamic mechanical properties. Its mechanical properties and energy absorption capacity have been tuned by means of formulation optimization, molecular dynamics (MD) simulation and the addition of reinforcing materials. Owing to the special molecular structure of polyurea, the mechanism of polyurea protection against blasts and impacts is the simultaneous effect of multiple properties. For different substrates and structures, polyurea needs to provide different performance characteristics, including adhesion, hardness, breaking elongation, etc., depending on the characteristics of the load to which it is subjected. 
  • 805
  • 11 Jul 2022
Topic Review
Waste Plastics’ Liquefaction into Fuel Fraction
Polymers and plastics are crucial materials in many sectors of our economy, due to their numerous advantages. They also have some disadvantages, among the most important are problems with the recycling and disposal of used plastics. The recovery of waste plastics is increasing every year, but over 27% of plastics are landfilled. The rest is recycled, where, unfortunately, incineration is still the most common management method. From an economic perspective, waste management methods that lead to added-value products are most preferred—as in the case of material and chemical recycling. Since chemical recycling can be used for difficult wastes (poorly selected, contaminated), it seems to be the most effective way of managing these materials. Moreover, as a result this of kind of recycling, it is possible to obtain commercially valuable products, such as fractions for fuel composition and monomers for the reproduction of polymers. 
  • 805
  • 06 Dec 2022
Topic Review
Blood–Brain Barrier Penetrating Nanoplatforms
The current knowledge and advancements on various nanoplatforms (NF) and the use of nanoparticles for successful cross of BBB to treat the brain-related disorders such as brain tumors, Alzheimer’s disease, Parkinson’s disease, and stroke. 
  • 799
  • 12 Jan 2021
Topic Review
Bio-Vitrimers for Sustainable Circular Bio-Economy
The traditional polymer circular economy (CE) continues to be challenging due to its reprocessing/recycle ability; also, at the same time, newly developed substitute materials have not expressed similar performance to conventional materials involved in contemporary applications. Hence, linear approaches such as “take-make-use-waste” have severely affected sustainability modules where non-renewable resources have been used at maximum levels. In addition, sustainability is termed along with the circular economy paradigm in recent times, although material sustainability differs from CE material. The circular economy mainly focuses on the economic, environmental and social impacts, whereas sustainability is more about an ecological importance. Globally, frameworks have been formed to enhance the sustainable environment. The United Nations (UN) has designed 17 sustainable development goals to be enforced in all countries in order to reach the goal of a sustainable society by 2030.
  • 797
  • 01 Nov 2022
Topic Review
Remediation of Textile-Dye-Containing Wastewater
Water makes up most of the Earth, although just 0.3% is usable for people and animals. The huge oceans, icecaps, and other non-potable water resources make up the remaining 99.7%. Water quality has declined due to pollution from population growth, industry, unplanned urbanization, and poor water management. The textile industry has significant global importance, although it also stands as a major contributor to wastewater generation, leading to water depletion and ecotoxicity. This issue arises from the extensive utilization of harmful chemicals, notably dyes.
  • 792
  • 09 Jan 2024
Topic Review
Design and Synthesis of Polyphosphodiesters
Polyacids containing –P(O)(OH)– fragment in the polymer backbone, or polyphosphodiesters (PPDEs), hold a special place among natural and synthetic polymers. The structural similarity of PPDEs to natural nucleic and teichoic acids, biocompatibility of PPDEs and their mimicking to biomolecules providing the ‘stealth effect’, high bone mineral affinity of PPDEs, and adjustable hydrolytic stability of PPDEs are the basis for various biomedical, industrial and household applications. Actual synthetic approaches to PPDEs are based on incredibly rich chemistry of organic phosphates and phosphonates, and include modern techniques such as catalytic ring-opening polymerization (ROP), acyclic diene metathesis (ADMET) polycondensation, and others.
  • 792
  • 09 Jan 2023
Topic Review
Molecular Weight of Polyamides
Polyamides (PAs) undergo local environmental degradation, leading to a decline in their mechanical properties over time. PAs can experience various forms of degradation, such as thermal degradation, oxidation, hydrothermal oxidation, UV oxidation, and hydrolysis. In order to better comprehend the degradation process of PAs, it is crucial to understand each of these degradation mechanisms individually.
  • 791
  • 09 Jan 2024
Topic Review
Thermodynamic Aspects Governing Shape Memory Elastomers
Shape memory elastomers have revolutionised the world since their introduction in the 20th century. The ability to tailor chemical structures to produce a family of materials in wide-ranging forms with versatile properties has propelled them to be ubiquitous.
  • 786
  • 02 Sep 2022
Topic Review
The Assembly of PPTA Nanofibers and the Applications
Poly (p-phenylene terephthalamide) (PPTA) is one kind of lyotropic liquid crystal polymer. Kevlar fibers made from PPTA is widely used in many fields due to the superior mechanical properties resulted from highly oriented macromolecular structure. However, the “infusible and insoluble” characteristic of PPTA gives rise to its poor processability, which limits its scope of application. The strong interactions and orientation characteristic of aromatic amide segments make PPTA attractive in the field of self-assembly. The chemical derivations have proved an effective way to modify the molecular structure of PPTA to improve its solubility and amphiphilicity, which resulted in different liquid crystal behaviors or supramolecular aggregates, but the modification of PPTA is usually complex and difficult. Alternatively, higher order all-PPTA structures have also been realized through the controllable hierarchical self-assembly of PPTA from the polymerization process to the formation of macroscopic products. It briefly introduces the self-assembly methods of PPTA based materials in recent years, and focuses on the polymerization-induced PPTA nanofibers which can be further fabricated into different macroscopic architectures when other self-assembly methods are combined. This monomer-started hierarchical self-assembly strategy evokes the feasible processing of PPTA, and enriches the diversity of product, which is expected to be expanded to other liquid crystal polymers.
  • 783
  • 20 Jul 2022
Topic Review
Gelatin-Based Hybrid Scaffolds
Gelatin is a biopolymer with interesting properties that have greatly attracted the attention of many biomedical researchers, such as low antigenicity, good biodegradability, and biocompatibility in the physiological environment. The gelatin-based materials offer excellent characteristics of wound dressings. The fast degradation time and highly hydrophilic surface make gelatin inappropriate as a base material for the development of wound dressings.
  • 781
  • 08 Sep 2021
Topic Review
Conducting Silicone-Based Polymers
Conducting polymers (CPs) are unique due to their ease of synthesis, environmental stability, and simple doping/dedoping chemistry. Electrically conductive silicone polymers are the current state-of-the-art for, e.g., optoelectronic materials. 
  • 780
  • 23 Apr 2021
Topic Review
Fully Implanted Hearing Systems
The ear and brain work together in the hearing process. Sound energy in the audible frequency range (20 Hz–20 kHz) propagates through air medium as an acoustical mechanical wave which enters from the outer ear towards the middle ear to vibrate the eardrum. 
  • 776
  • 02 Aug 2021
Topic Review
Antimicrobial Polymeric Structures
Certain natural and synthetic polymers are versatile materials that have already proved themselves to be highly suitable for the development of the next-generation of antimicrobial systems that can efficiently prevent and kill microbes in various environments.
  • 775
  • 28 May 2021
Topic Review
Sustainable Polymeric Food Packaging Films
Food packaging is fundamental to ensuring food distribution and protection around the world, especially when considering the solid growth of the population. Without packaging, food would easily spoil and the distribution of enormous quantities of food, raw and processed, to different areas around the globe would hardly be possible.
  • 773
  • 16 Jan 2023
Topic Review
Chromophoric Dendrimer-Based Materials
Dendrimers (from the Greek dendros → tree; meros → part) are macromolecules with well-defined three-dimensional and tree-like structures. Remarkably, this hyperbranched architecture is one of the most ubiquitous, prolific, and recognizable natural patterns observed in nature. 
  • 772
  • 16 Jan 2022
Topic Review
Preparation of Organosiloxane Telechelics by Cationic Ring-Opening Polymerization
Polydimethylsiloxanes (PDMS) telechelics are important both in industry and in academic research. They are used both in the free state and as part of copolymers and cross-linked materials. The most important, practically used, and well-studied method for the preparation of such PDMS is diorganosiloxane ring-opening polymerization (ROP) in the presence of nucleophilic or electrophilic initiators. Cationic ROP is also of interest for the preparation of functional PDMS. The advantage of this process is that it can be carried out at a relatively low temperature, the catalyst can be easily deactivated, and the process can also be used to synthesize polysiloxanes having base-sensitive substituents such as Si–H or Si–(CH2)3–SH.
  • 769
  • 24 Jun 2022
Topic Review
Natural Antibacterial Additives in Bioactive Wound Dressings
Wound care is a global health issue with a financial burden of up to US $96.8 billion annually in the USA alone. Chronic non-healing wounds which show delayed and incomplete healing are especially problematic. Natural products and their derivatives have long been a significant source of pharmaceuticals against AMR. Scrutinising the data of newly approved drugs has identified plants as one of the biggest and most important sources in the development of novel antibacterial drugs.
  • 768
  • 10 Mar 2023
Topic Review
Polyurea Aerogels
The term “aerogel” describes a certain class of low-density solid materials with a high open porosity. Aerogels can be considered to be a subclass of the much broader domain of porous materials; however, they are distinguished from, for example, blown foams, because they are prepared in a completely different manner—namely, by drying wet gels in a way that preserves nearly all of their volume in the final dry form.
  • 757
  • 02 Apr 2022
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