Film development

2014 ◽  
pp. 41-55
Keyword(s):  
Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 578
Author(s):  
Bilal Harieth Alrimawi ◽  
May Yee Chan ◽  
Xin Yue Ooi ◽  
Siok-Yee Chan ◽  
Choon Fu Goh

Rice starch is a promising biomaterial for thin film development in buccal drug delivery, but the plasticisation and antiplasticisation phenomena from both plasticisers and drugs on the performance of rice starch films are not well understood. This study aims to elucidate the competing effects of sorbitol (plasticiser) and drug (antiplasticiser) on the physicochemical characteristics of rice starch films containing low paracetamol content. Rice starch films were prepared with different sorbitol (10, 20 and 30% w/w) and paracetamol contents (0, 1 and 2% w/w) using the film casting method and were characterised especially for drug release, swelling and mechanical properties. Sorbitol showed a typical plasticising effect on the control rice starch films by increasing film flexibility and by reducing swelling behaviour. The presence of drugs, however, modified both the mechanical and swelling properties by exerting an antiplasticisation effect. This antiplasticisation action was found to be significant at a low sorbitol level or a high drug content. FTIR investigations supported the antiplasticisation action of paracetamol through the disturbance of sorbitol–starch interactions. Despite this difference, an immediate drug release was generally obtained. This study highlights the interplay between plasticiser and drug in influencing the mechanical and swelling characteristics of rice starch films at varying concentrations.


Author(s):  
Dieter E. Bohn ◽  
Norbert Moritz

A transpiration cooled flat plate configuration is investigated numerically by application of a 3-D conjugate fluid flow and heat transfer solver, CHT-Flow. The geometrical setup and the fluid flow conditions are derived from modern gas turbine combustion chambers. The plate is composed of three layers, a substrate layer (CMSX-4) with a thickness of 2 mm, a bondcoat (MCrAlY) with thickness 0,15 mm, and a thermal barrier coating (EB-PVD, Yttrium stabilized ZrO2) with thickness 0,25 mm, respectively. The numerical grid contains the coolant supply (plenum), the solid body, and the main flow area upon the plate. The transpiration cooling is realized by finest drilled holes with a diameter of 0,2 mm that are shaped in the region of the thermal barrier coating. The holes are inclined with an angle of 30°. Two different configurations are investigated that differ in the shaping of the holes in their outlet region. The numerical investigation focus on the influence of different turbulence models on the results. Regarding the secondary flow, the cooling film development and complex jet mixing vortex systems are analyzed. Additionally, the impact on the temperature distribution both on the plate surface and in the plate is investigated. It is shown that the choice of the turbulence model has a significant influence on the prediction of the flow structure, and, consequently, on the calculation of the thermal load of the solid body.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Varvara Gribova ◽  
Anastasiia Navalikhina ◽  
Oleksandr Lysenko ◽  
Cynthia Calligaro ◽  
Eloïse Lebaudy ◽  
...  

AbstractLayer-by-layer (LbL) deposition method of polyelectrolytes is a versatile way of developing functional nanoscale coatings. Even though the mechanisms of LbL film development are well-established, currently there are no predictive models that can link film components with their final properties. The current health crisis has shown the importance of accelerated development of biomedical solutions such as antiviral coatings, and the implementation of machine learning methodologies for coating development can enable achieving this. In this work, using literature data and newly generated experimental results, we first analyzed the relative impact of 23 coating parameters on the coating thickness. Next, a predictive model has been developed using aforementioned parameters and molecular descriptors of polymers from the DeepChem library. Model performance was limited because of insufficient number of data points in the training set, due to the scarce availability of data in the literature. Despite this limitation, we demonstrate, for the first time, utilization of machine learning for prediction of LbL coating properties. It can decrease the time necessary to obtain functional coating with desired properties, as well as decrease experimental costs and enable the fast first response to crisis situations (such as pandemics) where coatings can positively contribute. Besides coating thickness, which was selected as an output value in this study, machine learning approach can be potentially used to predict functional properties of multilayer coatings, e.g. biocompatibility, cell adhesive, antibacterial, antiviral or anti-inflammatory properties.


2015 ◽  
Vol 804 ◽  
pp. 179-182 ◽  
Author(s):  
Piyapong Pankaew ◽  
Pattarinee Klumdoung ◽  
Kittisakchai Naemchanthara

Silk sericin/chitosan composite films were successfully prepared for possible future wound dressing applications. To prepare the chitosan, shrimp shells were first washed and finely ground to obtain a fine powder before extracting the chitosan using a chemical reaction method. The sericin was extracted from Thai raw cocoons of Bombyx mori silk worm via boiling and drying. To prepare the silk sericin/chitosan composite films, the silk sericin and chitosan solutions with varying volume ratios were mixed in a magnetic stirrer for 30 minutes. They were then dropped on to a plastic mold. The sample was dried at a temperature of 50 °C. The prepared composite films were characterized using UV-VIS spectroscopy, Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscope (SEM). The results from our studies could provide a method for future composite film development.


2021 ◽  
Vol 12 (3) ◽  
pp. 269-285 ◽  
Author(s):  
Steffi Ebert

The dramaturgs of the Deutsche Film-Aktiengesellschaft (DEFA), the GDR’s state-owned film production company, played a particular role in socialist children’s film culture. Within the production process, they acted as important mediators as well as developed themes and defended them before the state film censors. In this article, I argue that screenwriting for children and the changing role of the dramaturg were remarkable inasmuch as the creative collaboration between authors, dramaturgs and directors became a collective process of navigating between politics, education, film and the young audience that can reasonably be described as ‘collective authorship’. First, I will show how DEFA children’s film production was an example of the ‘state-socialist mode of children’s film production’ and examine Szczepanik’s model in the light of the current question. Following this, I will examine the structural and practical development of children’s film production in view of both official images of the child and the images of children anticipated by the filmmakers. At the same time, I will discuss the role of dramaturgs as participants in a collective authorship process.


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