排序方式: 共有20条查询结果,搜索用时 15 毫秒
1.
2.
Johnsy George R. Kumar C. Jayaprahash A. Ramakrishna S. N. Sabapathy A. S. Bawa 《应用聚合物科学杂志》2006,102(5):4514-4522
Rice bran was incorporated into low‐density polyethylene (LDPE) at different concentrations by compounding in a twin‐screw extruder and blown into films of uniform thickness. The rice bran incorporation influenced physical, mechanical, barrier, optical, thermal properties, and biodegradation of LDPE. The mechanical and optical properties decreased as the percentage of rice bran increased. The effect of rice bran on the morphology of LDPE blends was examined using scanning electron microscopy. Oxygen transmission rate and water vapor transmission rate increased with the increased content of rice bran. Addition of rice bran did not alter the melting temperature (Tm) of the blends; however the thermal stability decreased, while glass transition temperature (Tg) increased. Kinetics of thermal degradation was also investigated and the activation energy for thermal degradation indicated that for up to 10% filler addition, the dispersion and interfacial adhesion of rice bran particles in LDPE was good. Aerobic biodegradation tests using municipal sewage sludge and biodegradation studies using specific microorganism (Streptomyces species) revealed that the films are biodegradable. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4514–4522, 2006 相似文献
3.
CO2‐induced crystal engineering of polylactide and the development of a polymeric nacreous microstructure 下载免费PDF全文
Nacre's biomineralization process and its self‐organizing brick‐and‐mortar crystalline microstructure have inspired many researchers to develop new materials derived from the natural world. In our study, we took a novel approach to two‐dimensional (2‐D) crystallization. That is, we applied the biomineralization self‐organizational principle that exists in natural materials to a biopolymer (polylactide). The CO2‐induced crystallization of poly(d ‐lactide), with its unique diffusion‐controlled crystallization mechanism, tends to produce distinct 2‐D spherulitic structures. We found that these 2‐D spherulites were self‐organizing in nature, and that they created a stack of 2‐D spherulitic structures. These crystalline microstructures, with their intervening amorphous phase, were foamed in situ due to the CO2‐induced crystallization self‐exclusion phenomenon. We compared the resultant crystalline structure with nacre's brick‐and‐mortar crystalline microstructure to confirm the biomimetic principle of self‐organization. To the best of our knowledge, this is the first time that a biopolymer has been crystallized in a 2‐D manner in a way that resembles nature's biomineralization process. The hierarchical crystalline microstructure is morphologically similar to that of nacre biomaterials. This novel crystallization technique is simple, absolutely non‐toxic and works swiftly to produce a brick‐and‐mortar crystalline microstructure with a high degree of order. © 2017 Society of Chemical Industry 相似文献
4.
Effect of Pasteurization and Retort Processing on Spectral Characteristics,Morphological, Thermal,Physico‐Mechanical,Barrier and Optical Properties of Nylon‐Based Food Packaging Materials 下载免费PDF全文
Rajamanickam Ramalingam Sajeevkumar VA Johnsy George Sabapathy SN 《Packaging Technology and Science》2015,28(5):425-436
The effect of pasteurization and retort processing on spectral, morphological, thermal, physico‐mechanical, barrier and optical properties of three different packaging materials viz., PP/N6/PP, PET/N6/cPP and SiOx‐PET/N6/cPP were studied. These packaging materials were packed with distilled water, which acted as a food simulant. Subsequently, these pouches were subjected to different thermal processing conditions such as pasteurization and retort processing. Both the processing techniques found to have retained the mechanical properties of all packaging materials. Water vapour transmission rate (WVTR) and oxygen transmission rate (OTR) of nylon‐based combinations were increased after processing. Gloss found to decrease invariably irrespective of the material and increases with the severity of the treatment. XRD diffractogram shows changes in crystal structure as a result of thermal processing, and SEM analysis shows the crystal fragmentation. Absorption of water by the amide group of nylon 6 was observed, which could be a reason for the increase in OTR and WVTR. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
5.
English RD Van Stipdonk MJ Sabapathy RC Crooks RM Schweikert EA 《Analytical chemistry》2000,72(24):5973-5980
We show that selected self-assembled monolayers (SAMs) and bilayers are readily characterized by the application of controlled photooxidation and spontaneous desorption mass spectrometry (SDMS) in the negative ion mode. Additionally, SDMS is used to characterize organic and inorganic anionic species adsorbed to the surface of a positively charged SAM surface, 2-aminoethanethiol (AET). Prominent peaks are observed that correspond both to the sulfonate form of each SAM and bilayer and to the anion form of each molecule adsorbed to AET. In addition, fragments of the oxidized thin films were also observed at m/z 80 (SO3-) and 97 (HSO4-). Other prominent fragment peaks more characteristic of the molecule are also seen in the mass spectra. 相似文献
6.
CO2‐induced crystallization of polylactide and its self‐templating ‘stack of coins’ crystalline microstructure 下载免费PDF全文
Sabapathy Sankarpandi Chul B. Park Anup K. Ghosh 《Polymer Engineering and Science》2017,57(4):365-373
Can we learn from biomineralization process of natural materials to fabricate a three‐dimensional (3D) thick laminate microstructure by stacking of two‐dimensional (2D) crystalline structure? By adopting this self‐organization principle of biomineralization process, a polymer is crystallized two‐dimensionally into a multi‐layered architecture. Herein, we demonstrate a 2D crystallization method of polylactide and its principle of self‐organization to develop the discontinuous laminate microstructures. We find that instead of building a multilayered morphology layer‐by‐layer, the lamellar microstructures can be built in one step by using self‐organization principle of 2D crystallization. The biopolymer PLA is compression molded, and the molded samples are crystallized by using supercritical CO2 in a high pressure vessel. The CO2‐induced crystallization has a unique diffusion‐controlled crystallization mechanism, which tends to produce a disc‐shape spherultic structure. From microscopy analysis, we observe that these 2D spherulites are self‐organizing in nature and form 3D thick laminate structures with integrated amorphous phase in between. The obtained discontinuous laminate microstructure is comparable to “stack of coins” structure and we report the biomimetic approach of crystallization process. Thus, our study shows an innovative approach to engineer the crystalline microstructure of PLA. POLYM. ENG. SCI., 57:365–373, 2017. © 2016 Society of Plastics Engineers 相似文献
7.
Devi S. Malarvezhi P. Dayana R. Vadivukkarasi K. 《Wireless Personal Communications》2020,114(3):2121-2133
Wireless Personal Communications - Over the past decades Machine Learning and Deep Learning algorithm played a vital part in the development of Autonomous Vehicle. It is indeed for the perception... 相似文献
8.
9.
Dayana R. Malarvezhi P. Vadivukkarasi K. Kumar R. 《Wireless Personal Communications》2020,114(3):2105-2119
Wireless Personal Communications - Express evolution in smart wireless communication address the issue of spectrum scarcity. Implementation of cognitive radio (CR) is one of the promising... 相似文献
10.
Sivarambabu P. V. Malarvezhi P. Dayana R. Vadivukkarasi K. Rao P. Rama Koteswara 《Wireless Personal Communications》2022,122(1):897-914
Wireless Personal Communications - The importance of 5G communication in today's world is requisite. The communication over 4G communications has led to congestion and will not meet the demands... 相似文献