Production Of Synthetic Polymers Research Articles

Microplastic Sources, Reduction and Remediation: Current State and Future Trends

Plastic waste (PW) and microplastics (MPs) pollution represent one of the main ecological challenges and thus attract society's increasing attention. The exponential growth of plastics' presence and its small (1 μm – 5 mm) particles (MPs) in the environment and inhabiting species is a consequence of linear economy employment. The circular economy has been proposed as the promising route to using plastics more sustainably, and its implementation in the plastic management system is imposed to reduce MPs release. As MPs are emitted in all phases of the plastic life cycle, actions at all levels of the value chain are necessary. Prioritizing the entire plastic value chain also became the goal of more recent plastic pollution regulations, contrary to the previous ones, primarily prohibiting particular plastic items. The microplastic minimization strategy follows an upside-down pyramid, beginning with prevention, then reducing, reusing, recycling, recovering, and finally disposal, which is the least desired alternative. New technologies development for synthetic polymer production and remediation technologies innovations are another key component of the circular economy model. This study outlines microplastics' primary and secondary sources, summarizes the current methods for MPs elimination from different media along with their benefits and drawbacks, and highlights the importance of circular economy principles employment to minimize the MPs' pollution and their possible environmental repercussions.

Optimization and analysis of dual-enzymatic synthesis for the production of linear glucan

Linear α-glucan (LG), a linear polymer linked by α-1,4 bonds, has received increasing attention for its potential applications in synthetic polymer production. Notably, the functionality of LG is strongly influenced by its degree of polymerization (DP). In this study, SP and GP were successfully constructed and expressed. The reaction of enzymatic co-polymerization into LG was investigated. The preferred reaction was carried out at 37 °C and pH 7.4 for 72 h, with a maximum conversion rate of 25 %. Afterwards, two approaches were used to modulate the molecular structures of LGs. Firstly, LGs with distinct molecular weights ranging from 1062.33 ± 16.04 g/mol to 5679 ± 80.29 g/mol were obtained by adjusting the substrate/primer ratio during the LG synthesis process. Secondly, two distinct products could be produced by altering the enzyme addition method: short-chain LG with a DP < 10 (64.34 ± 0.54 %) or long-chain LG with a DP > 45 (45.57 ± 2.18 %). Additionally, theoretical synthesis model was constructed which subdivided the reaction into three stages to evaluate this dual-enzyme cooperative system. These findings have significant implications in promoting the application of LG in the fields of biomedicine and material science.

Artificial neural network-based mechanical properties prediction of cellulose polyvinyl alcohol bio composite

The deliberation of the environmental effect on synthetic polymer products has effectuated the development of the latest materials obtained from natural resources. This work tested the compatibility of a bio composite of polyvinyl alcohol (PVA) and cellulose. The mechanical effect of cellulose on PVA was investigated in the Synthia module of BIOVIA material studio and Artificial neural network. The exacted shear and bulk modulus were obtained with the variation of mass fraction of cellulose from 0 to 1 mass%. At 1% mass fraction of cellulose, the mechanical properties of PVA like shear modulus and bulk modulus had increased to 401% and 130%, respectively. The dry lab values of shear and bulk modulus were further analysed through a Bi-layer Artificial Neural Network (ANN). The designed ANN successfully predicted the bulk and shear modulus values. The implemented ANN prevailed with a root mean square error of 2.0692 and 1.865 for both properties.

Waste of brewing production - a coagulating agent in the technology of extraction of emulsion rubbers from latex

Today, there is a growing interest in the production of synthetic polymers, which are widely used in the production of modern materials. Of particular interest is the manufacture of rubbers by emulsion polymerization. Rubber compounds and vulcanizates made on their basis have characteristics due to which they are actively used in various industrial sectors. The coagulation process in the production of emulsion polymers increases environmental stress. Sodium chloride used at some enterprises as a coagulating agent is consumed in large quantities - up to 200 kg / t of rubber, and increases environmental pollution. In the presented work, for the first time, the possibility of recycling the beer production residue - inactivated yeast, which is proposed to be used to reduce the aggregative stability of disperse systems, is considered. The introduction of yeast into the emulsion polymer isolation technology makes it possible to reduce the amount of sodium chloride in the waters discharged from the enterprise. The use of a system based on a protein coagulant contributes to the complete release of coagulum from latex at a consumption of inactivated yeast in the amount of 10-15 kg/t of rubber. The most effective results were obtained when yeast preliminarily acidified with sulfuric acid was used in this process, which led to the charging of the nitrogen atom of the protein component. It is noted that the best temperature regime for the process of coagulation of latex particles is 1-20 ℃. An increase in temperature to 60 ℃ leads to an increase in the consumption of coagulant up to 25 kg/t of rubber. The ratios of the consumption of sulfuric acid and acidified yeast have been optimized, allowing to obtain the most complete coagulation of the latex. It has been established that the rubbers isolated using food production waste meet the requirements for rubbers of the SKS-30ARK brand according to the main physical and mechanical indicators.

Application of brewing waste in the technology of synthetic polymers

At present, much attention is paid to the production of synthetic polymers. The production of rubbers by emulsion polymerization is of particular interest. Sodium chloride, currently used as a coagulating agent, has a high consumption of up to 200 kg / t of rubber and increases environmental pollution. In the presented work, for the first time, the possibility of using dispersed systems of brewing waste (yeast) to reduce the aggregate stability is considered. The use of waste material in the technology of extracting rubber from latex makes it possible to exclude sodium chloride from the technological cycle. The use of a system based on a protein coagulant makes it possible to achieve complete separation of rubber from latex at a waste consumption of 10-15 kg / t of rubber. The best results were achieved when yeast pre-acidified with sulfuric acid was used in this process, which leads to charging the nitrogen atom of the protein component. It was noted that the best temperature regime for the process of rubber extraction from latex is 1-20 ° C. An increase in temperature to 60 ° C leads to an increase in the consumption of coagulant by 5 kg / t of rubber. According to all the main physical and mechanical indicators, rubbers isolated by this technology meet the requirements.

Application of Colloidal Chemistry and Polymer Chemistry in Papermaking Industry

Colloidal chemistry is a science to study the physicochemical properties of generalized colloidal dispersion systems. Polymer chemistry is a new comprehensive subject that studies the synthesis, chemical reaction, physical chemistry, physics, processing and application of polymer compounds. The development of polymer chemistry mainly experienced four periods: the utilization and processing of natural polymers, the modification of natural polymers, the production of synthetic polymers and the establishment of polymer science. Since the 1930s, with the development of synthetic polymers, polymer related sub disciplines such as reaction kinetics, chemical thermodynamics, structural chemistry, polymer physics and biopolymers have been gradually established, forming a systematic polymer science. Papermaking industry is an industrial sector that manufactures all kinds of paper and paperboard. It includes the pulp manufacturing industry that uses wood, reed, bagasse, straw, wheat straw, cotton straw, hemp stalk, cotton and other raw materials to manufacture pulp, the paper and paperboard industry, and the processing paper manufacturing industry that produces coated, polished, glued, laminated and other processing paper and font paper plate. Paper industry is an important industry closely related to the development of national economy and the construction of social civilization. This paper focuses on the relationship between colloidal chemistry, polymer chemistry and papermaking industry, especially its application in cooking, washing, bleaching, papermaking and water treatment, and introduces in detail the current situation and development trend of flocculation method for papermaking wastewater according to colloidal chemistry theory.

2011-2019년 식품용 기구 및 용기·포장의 제외국 부적합 정보 분석

The foreign trends of noncompliance occurring frequently in food contact materials during the period of 2011-2019 was investigated by analyzing the food safety risk information DB in the National Food Safety Information Service (NFSI). A total of 2,042 cases of noncompliance of food utensils, containers, and packages were classified into 5 violation categories; administrative procedures, manufacturing and processing standards, residues and migration standards, labeling and advertising, and quality standards. This was again subcategorized according to non-compliance causative factors. The non-compliances in residues and migration standards comprised the largest proportion (76.4%) of the violative categories. The number of noncompliance information collected in 2011 was 88 cases and increased to 373 cases in 2019. A 72.8% of the non-compliance case was identified to be products of 4 countries (China 64.2%, Germany 4.0%, Japan 3.2%, and Taiwan 3.1%), those produce large quantities of containers and packaging products. During the period of 2011-2019, the number of illegal use of hazardous materials and illegal recycling of waste synthetic resins has decreased to less than one a year since 2014. On the other hand, after 2016, inconsistency of heat-resisting temperature labeling (Taiwan), non-compliance in paper container’s strength standards, violation of printing standards, and the risk of consumer injury while using the products were newly reported due to the strengthening of consumer safety protection regulations. Migration of hazardous substances in synthetic polymer products such as heavy metals, melamine and formaldehyde in melamine tableware, primary aromatic amines which are colorant components in kitchenware such as ladles and spatulas, and phthalate plasticizers have been continuously reported with high frequency.

Establishing Efficient Bisphenol A Degradation by Engineering Shewanella oneidensis

Bisphenol A (BPA) has been widely used as a plasticizer in the production of synthetic polymers, such as those used in food storage containers and bottles. However, BPA interferes with endocrine sy...

Waste Reutilization in Polymeric Membrane Fabrication: A New Direction in Membranes for Separation.

In parallel to the rapid growth in economic and social activities, there has been an undesirable increase in environmental degradation due to the massively produced and disposed waste. The need to manage waste in a more innovative manner has become an urgent matter. In response to the call for circular economy, some solid wastes can offer plenty of opportunities to be reutilized as raw materials for the fabrication of functional, high-value products. In the context of solid waste-derived polymeric membrane development, this strategy can pave a way to reduce the consumption of conventional feedstock for the production of synthetic polymers and simultaneously to dampen the negative environmental impacts resulting from the improper management of these solid wastes. The review aims to offer a platform for overviewing the potentials of reutilizing solid waste in liquid separation membrane fabrication by covering the important aspects, including waste pretreatment and raw material extraction, membrane fabrication and characterizations, as well as the separation performance evaluation of the resultant membranes. Three major types of waste-derived polymeric raw materials, namely keratin, cellulose, and plastics, are discussed based on the waste origins, limitations in the waste processing, and their conversion into polymeric membranes. With the promising material properties and viability of processing facilities, recycling and reutilization of waste resources for membrane fabrication are deemed to be a promising strategy that can bring about huge benefits in multiple ways, especially to make a step closer to sustainable and green membrane production.

Yeni 2-Metoksi-6-[(3-alkil/aril-4,5-dihidro-1H-1,2,4-triazol-5-on-4-il)-azometin]fenil Furan-2-karboksilat Türevlerinin Sentezi ve in vitro Antioksidan Aktiviteleri

1,2,4-Triazol ve 4,5-dihidro-1H-1,2,4-triazol-5-on halkası taşıyan heterosiklik bileşikler çok geniş bir spektrumda biyolojik aktivite göstermektedir. Schiff bazlarının ise boya, tekstil, kozmetik, analitik reaktifler, su iyileştirme ürünleri, petrol katkı maddeleri, sentetik polimer ürünleri, deri ve kağıt gibi doğal makromoleküler materyallerin iyileştirilmesi gibi çeşitli pratik uygulamaları bulunmaktadır. Ancak Schiff Bazlarının en önemli uygulama alanı ilaç kimyasıdır. Potansiyel biyolojik aktif 1,2,4-triazol halkası içeren Schiff bazlarının birçok hastalığın tedavisinde kullanılabilecek faydalı moleküllerin ve ileride hastalıkların tedavisinde kullanılabilecek ilaçların elde edilmesi ümit edilmektedir. Bu amaçla 3-alkil(aril)-4-amino-4,5-dihidro-1H-1,2,4-triazol-5-on’ların (1), 2-formil-6-metoksifenil furan-2-karboksilat (2) ile reaksiyonundan 2-metoksi-6-[(3-alkil/aril-4,5-dihidro-1H-1,2,4-triazol-5-on-4-il)-azometin]fenil furan-2-karboksilatlar (3) elde edilmiştir. Daha sonra 3 bileşiklerinin asetilasyon reaksiyonları incelenerek 2-metoksi-6-[(1-asetil-3-alkil/aril-4,5-dihidro-1H-1,2,4-triazol-5-on-4-il)-azometin]fenil furan-2-karboksilatlar (4) sentezlenmiştir. On dört yeni bileşiğin yapıları IR, 1H NMR, 13C NMR ve UV spektral verileri kullanılarak aydınlatılmıştır. Ayrıca, sentezlenen 3 ve 4 tipi yeni bileşiklerin üç farklı yöntemle (indirgeme gücü, serbest radikal giderme aktivitesi ve metal şelat aktivitesi) in vitro antioksidan özellikleri değerlendirilmiştir.

High-performance Technologies of Biodegradable Plastics to Solve the Ocean Contamination by Plastics

The high economic growth of the 20th century has led to three big problems, exhaustion of oil reserves, increases in greenhouse gas emission, and solid waste management, in consequence of the mass production, mass consumption, and mass disposal of conventional synthetic polymer products made from oil as their feedstock source.

Polyethylene microplastics do not increase bioaccumulation or toxicity of nonylphenol and 4-MBC to marine zooplankton.

Global production of synthetic polymers, led by polyethylene (PE), rose steadily in the last decades, and marine ecosystems are considered as a global sink. Although PE is not biodegradable, in coastal areas it fragments into microplastics (MP) readily taken up by biota, and have been postulated as vectors of hydrophobic chemicals to marine organisms. We have tested this hypothesis using two organisms representative of the marine plankton, the holoplanktonic copepod Acartia clausi, and the meroplanktonic larva of the Paracentrotus lividus sea-urchin, and two model chemicals with similar hydrophobic properties, the 4-n-Nonylphenol and the 4-Methylbenzylidene-camphor used as plastic additive and UV filter in cosmetics. Both test species actively ingested the MP particles. However, the presence of MP never increased the bioaccumulation of neither model chemicals, nor their toxicity to the exposed organisms. Bioaccumulation was a linear function of waterborne chemical disregarding the level of MP. Toxicity, assessed by the threshold (EC10) and median (EC50) effect levels, was either independent of the level of MP or even in some instances significantly decreased in the presence of MPs. These consistent results challenge the assumption that MP act as vectors of hydrophobic chemicals to planktonic marine organisms.

Metal Free Reversible-Deactivation Radical Polymerizations: Advances, Challenges, and Opportunities.

A considerable amount of the worldwide industrial production of synthetic polymers is currently based on radical polymerization methods. The steadily increasing demand on high performance plastics and tailored polymers which serve specialized applications is driven by the development of new techniques to enable control of polymerization reactions on a molecular level. Contrary to conventional radical polymerization, reversible-deactivation radical polymerization (RDRP) techniques provide the possibility to prepare polymers with well-defined structures and functionalities. The review provides a comprehensive summary over the development of the three most important RDRP methods, which are nitroxide mediated radical polymerization, atom transfer radical polymerization and reversible addition fragmentation chain transfer polymerization. The focus thereby is set on the newest developments in transition metal free systems, which allow using these techniques for biological or biomedical applications. After each section selected examples from materials synthesis and application to biomedical materials are summarized.

Sublethal concentration of bisphenol A induces hematological and biochemical responses in an Indian major carp Labeo rohita

Bisphenol A (BPA), an organic compound which is widely used in the production of synthetic polymers, has been detected in surface water, sediments and biota and emerged as a ubiquitous contaminant in the aquatic environment. In the present study, Labeo rohita was exposed to sublethal concentration of BPA and hematological and biochemical responses were studied. The median lethal concentration of BPA to L. rohita was evaluated by probit analysis method and the value was calculated as 7.3mg/L for 24h. Fish were exposed to a sublethal concentration of 0.73mg/L (1/10th of the 24h LC50 value) of BPA for 35 days and hemato-biochemical and marker enzyme assays was performed at the end of 7, 14, 21, 28 and 35 days. The results revealed that there was a significant (P<0.05) decrease in hematological (hemoglobin, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin) and biochemical (protein) parameters in the BPA treated fish compared to control groups. White blood cells, glucose, aspartate aminotransferase, alanine aminotransferase and lactate dehydrogenase parameters were enhanced in experimental fish relative to control groups. However, the response of red blood cells, mean corpuscular hemoglobin concentration and gill Na+/K+-ATPase activity were found to be biphasic. In conclusion, the present investigation showed that analysis of hematological and biochemical parameters can be used as biomarkers for monitoring of BPA in the aquatic ecosystem.

Ecological Approaches in Textile Sector: The Effect of r-PET Blend Ratio on Ring Spun Yarn Tenacity

As the strategy of waste-management, it is very important to ensure that waste materials are recycled and reused in different industry in order to protect the ecological environment and there are so many initiatives related to this subject. Especially in the textile industry, recycling of PET bottle waste into recycled polyester fiber (r-PET) has made a difference in the industry to reduce load on environment pollution. In addition, it contributes to reducing the fossil fuels sources, water and energy which is the required amount in the production of synthetic polymers. With supporting these attempts, we have to fulfill our social responsibility in order to preserve the ecological balance. This study aims to compare the tenacity and elongation properties of ring spun yarns produced from r-PET fibers recycled from waste PET bottles and cotton fiber at different blend ratios. Besides, virgin PET fibers were also used to conduct the difference between recycled and virgin fibers. Both r-PET and virgin PET fibers were blended with cotton as 100%, 70%/30%, 50%/50% and 30%/70% ratios. All production parameters were constant to determine the effect of raw materials on yarn tenacity and elongation. Results showed that ring spun yarns containing r-PET fibers had lower tenacity and elongation than virgin PET. On the other hand, the quality parameters of r-PET fibers can be improved by technological developments, and so they will be preferred to preserve the ecological balance.

The Mechanical Properties of Alkaline Treated Pineapple Leaf Fibre to Reinforce Tapioca Based Bioplastic Resin Composite

The depletion crude oil has urged many researchers to find a suitable material to replace the current synthetic polymer products. Furthermore the shortage of landfill and ingestion of plastic by animals has to be taken in consideration in finding a material that can be easily biodegraded by enzyme or bacteria. In this study both fibre and matrix are from plant fibre, which makes the product highly compostable after the intended life usage. The fibre surface is modified with various alkaline concentrations before mixing with matrix through extrusion technique. The product of the extrusion is pelletized and hot compressed into specimen size according to ASTM. The specimen was tested for mechanical properties and the result shows the alkaline concentration affects the strength of the composite.

Advances in electrospinning: The production and application of nanofibres and nanofibrous structures

ABSTRACTThe use of electrospun nanofibres in applications such as medical products, fuel cells, photocatalysis, filtration, sensors and actuators is reviewed. Yarn production is classified into two types, namely hollow and core-shell structures; the methods used for producing the two structures for different polymers are discussed. Explanations are given for the various arrangements for producing nanofibre yarns and bundles in non-twisted or twisted forms to suit their end use. Natural and synthetic polymer products for biomedical uses and their applications in the form of polymer nanofibres are reviewed and polymeric optical fibres for use in photonic devices and optical circuits are evaluated. The production and development of nanofibrous filtration devices is explored with specific reference to water treatment and the control of air pollution. Particular attention is then given to the evaluation of different electrospinning methods for PVDF (polyvinylidene fluoride), a piezoelectric polymer widely used in sensor applications in terms of their ability to harvest more energy after agitation of the sensor and the effects of different additives on the piezoelectric properties of PVDF. Priorities for further research are then outlined.

English

Polymers form the backbones of plastic materials, and are continually being employed in an expanding range of areas. As a result, many researchers are investing time into modifying traditional materials to make them more user-friendly, and into designing novel polymer composites out of naturally occurring materials. A number of biological materials may be incorporated into polymer materials. In recent years, there has been a marked increase in interest in biodegradable bio-composite material for use in packaging, agriculture, medicine, and other areas. The belief is that polymer bio-composite materials will reduce the need for synthetic polymer production (thus reducing pollution) at a low cost, thereby producing a positive effect both environmentally and economically. This review is intended to provide a brief outline of work that is under way in the area of polymer bio-composite research and development, the scientific theory behind these materials, areas in which this research is being applied, and future work that awaits.

Natural Fibers and Biopolymer

In recent years, there have been a tremendous increase in interest, research and development in the natural fiber, biopolymers and polymers materials for their use in bio-composite, packaging, agriculture, medicine etc. Many scientists are modifying traditional materials to more user-friendly and novel polymer composites out of naturally occurring materials. Low recycling rates and the high volume of non-degradable plastics have shortened dramatically the life expectancy of current commercial landfills and increased the demand of biodegradable plastic packaging materials. A number of biological materials may be incorporated into biodegradable polymer materials like cellulose, starch and fiber extracted from various plants. The aim behind these judicious and planned efforts are to procure andpromote the biodegradable polymer materials that would reduce the need for the synthetic polymer production while reducing the pollution at a lower cost . This paper provides an insight to the progress in process in the field of the utilization of natural fiber and biodegradable polymer.

Film Sensor Device Fabricated by a Piezoelectric Poly(L-lactic acid) Film

Synthetic piezoelectric polymer films produced from petroleum feedstock have long been used as thin-film sensors and actuators. However, the fossil fuel requirements for synthetic polymer production and carbon dioxide emission from its combustion have raised concern about the environmental impact of its continued use. Eco-friendly biomass polymers, such as poly(L-lactic acid) (PLLA), are made from plant-based (vegetable starch) plastics and, thus, have a much smaller carbon footprint. Additionally, PLLA does not exhibit pyroelectricity or unnecessary poling. This suggests the usefulness of PLLA films for the human–machine interface (HMI). As an example of a new HMI, we have produced a TV remote control using a PLLA film. The intuitive operation provided by this PLLA device suggests that it is useful for the elderly or handicapped.