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A typical stress–strain curve for polymer film undergoing tensile strain testing  

A typical stress–strain curve for polymer film undergoing tensile strain testing  

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Soluplus® is a novel amphiphilic polymer that has been shown to enhance the solubility and drug dissolution rate of poorly soluble drugs. However, there still is a lack of information regarding the physical mechanical properties of Soluplus® with addition of the plasticizers. This study characterized the mechanical properties of Soluplus® with four...

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... The geometry of the rock slices to be tested was first considered. First, we used the method of making material sheets, following previous studies (Brace 1964;Lim and Hoag 2013), including making barbell samples and preset notches (Fig. 4a). However, this kind of sample has the disadvantage that it is easily destroyed at various diameters. ...
... The geometry and dimensions of granite slices. a Conventional tensile samples used in the study of materials(Brace 1964;Lim and Hoag 2013). b The granite slices used in this paper. ...
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... In Figure 4a, the comparison between two methods of obtaining the strain of materials is shown, the true strain and the linear strain. We show here that up to 49% of errors can be obtained when the proper strain equation is not used, which unfortunately is a prevalent mistake in the literature [34,[36][37][38]. In order to mitigate this problem, we show that the linear strain equation should be used when the maximum of up to 60% of strain (lf) is obtained concerning the initial specimen (l0). ...
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The growing environmental concern with the inappropriate disposal of conventional plastics has driven the development of eco-friendly food packaging. However, the intrinsic characteristics of polymers of a renewable origin, e.g., poor mechanical properties, continue to render their practical application difficult. For this, the present work studied the influence of ionic strength (IS) from 0 to 500 mM to modulate the physicochemical properties of methylcellulose (MC). Moreover, for protection against biological risks, Nisin-Z was incorporated into MC’s polymeric matrices, providing an active function. The incorporation of salts (LiCl and MgCl2) promoted an increase in the equilibrium moisture content in the polymer matrix, which in turn acted as a plasticizing agent. In this way, films with a hydrophobic surface (98°), high true strain (85%), and low stiffness (1.6 mPa) can be manufactured by addition of salts, modulating the IS to 500 mM. Furthermore, films with an IS of 500 mM, established with LiCl, catalyzed antibacterial activity against E. coli, conferring synergism and extending protection against biological hazards. Therefore, we demonstrated that the IS control of MC dispersion presents a new alternative to achieve films with the synergism of antibacterial activity against Gram-negative bacteria in addition to flexibility, elasticity, and hydrophobicity required in various applications in food packaging.
... 2 The inclusion of plasticizers could increase processability (lowering the glass transition temperature) and mechanical performance (elongation at break) of the polymer. 3 To achieve this performance, the plasticizer must be compatible with the polymer framework. PVDF is a rigid polymer that has a limited free volume. ...
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... At absorption stage, the presence of hydrophilic functional groups lead to a water permeation into the scaffolds. The water act as a plasticizer which can increase the free volume between polymer chains and increase the chains mobility [52,53]. The penetration of water starts the hydrolysis process through interactions of the water molecules with hydrolyzable bonds in crosslinks, side chains and backbone of the polymers, leading to producing some degradation products and a more mobility in the polymer chains [54,55]. ...
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... Mechanical properties of polymeric films can be defined in terms of Young's modulus, percentage of elongation, tear-resistance, and tensile strength (38,39). Various factors like the film-forming factor, type of manufacturing process, film thickness, and type and amount of drug in film formation should precisely be considered for controlling the mechanical strength of the film (40). ...
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... The removal of unpolymerized monomers by the washing process also influences the mechanical properties of the material, which is clearly shown in the analysis of the uniaxial tensile tests. Unpolymerized mono-and oligomers can act as plasticizers that lower the intermolecular forces between the polymer chains and increase material flexibility [53,54]. The removal of the residual monomers during the washing procedure results in a loss of flexibility and in an increase in the elastic modulus of the material. ...
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Novel fabrication techniques based on photopolymerization enable the preparation of complex multi-material constructs for biomedical applications. This requires an understanding of the influence of the used reaction components on the properties of the generated copolymers. The identification of fundamental characteristics of these copolymers is necessary to evaluate their potential for biomaterial applications. Additionally, knowledge of the properties of the starting materials enables subsequent tailoring of the biomaterials to meet individual implantation needs. In our study, we have analyzed the biological, chemical, mechanical and thermal properties of photopolymerized poly(ethyleneglycol) diacrylate (PEGDA) and specific copolymers with different photoinitiator (PI) concentrations before and after applying a post treatment washing process. As comonomers, 1,3-butanediol diacrylate, pentaerythritol triacrylate and pentaerythritol tetraacrylate were used. The in vitro studies confirm the biocompatibility of all investigated copolymers. Uniaxial tensile tests show significantly lower tensile strength (82% decrease) and elongation at break (76% decrease) values for washed samples. Altered tensile strength is also observed for different PI concentrations: on average, 6.2 MPa for 1.25% PI and 3.1 MPa for 0.5% PI. The addition of comonomers lowers elongation at break on average by 45%. Moreover, our observations show glass transition temperatures (Tg) ranging from 27 °C to 56 °C, which significantly increase with higher comonomer content. These results confirm the ability to generate biocompatible PEGDA copolymers with specific thermal and mechanical properties. These can be considered as resins for various additive manufacturing-based applications to obtain personalized medical devices, such as drug delivery systems (DDS). Therefore, our study has advanced the understanding of PEGDA multi-materials and will contribute to the future development of tools ensuring safe and effective individual therapy for patients.
... Effect of concentration of plasticizer on T g a) Triethyl citrate b) Polyethylene glycol c) Acetyl monoglyceride and d) Glycerol[33,65,[67][68][69][70][145][146][147][148]. ...
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The protection of pharmaceutical drugs by coating with suitable coating powder polymers plays a crucial role in the pharmaceutical industry. The dry coating is preferred due to its advantages, like reducing the overall coating amount and curing time. This has been an alternative method to liquid base coating techniques. Recently, pharmaceutical industries have been attracted to advances in the dry coating, i.e. Electrostatic dry powder coating. The peer-review summarized the adoption of the dry coating process, which involves the dry powder coating, hot-melt extrusion process, and electrostatic dry powder coating of tablets/pellets and their influencing parameters to achieve a fruitful product. To summarize this review, all the data extracted from previous journals, and parameters that influence the coating efficiency, drug release rate, ageing phenomenon, etc., have been highlighted.
... Both the parameters of tensile strength and elongation play an important role in the desired polymer to act as a good packaging material. 39 The homogenous addition from 1 to 2 wt% NBCPs increases the flexibility of polymer compared to the highest PCL NBCPs. The crosslinking polymer of PCL@-PEO-PAAs NBCPs can affect the increment of tensile strength and elongation with the growth of toughness. ...
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This work aims to design robust and biocompatible nano block-copolymers (NBCPs) of polycaprolactone@-polyethylene oxide-polyaminoacid (PCL@-PEO-PAAs) by ring-opening polymerization. Mechanical behavior including modulus, elongation at yield and break of the tetra block copolymer are studied at room temperature. The significant result lies when the extension at break is reduced by four times with an addition of 2 and 3 wt% of PCL respectively. The tensile strength at yield is found to be 22.39 ± 3.6 MPa, 34.66 ± 5.8 MPa, and 22.906 ± 4.1 MPa for 1, 2, and 3 wt% PCL@-PEO-PAAs NBCPs respectively. The partial hydrophobic nature of designed 3 wt% NBCP plays an important role in decreasing the strain at break and increasing the elongation at break of the composites compared to other 1 and 2 wt% NBCPs. In vitro cytotoxicity is observed to be more effective in irregular spheroid shaped 2 wt% compared to 1 and 3 wt% NBCPs due to a greater number of the amphiphilic groups present in the PCL grafted PEO-PAAs nano BCPs. The ζ potential value for 3, 2, and 1 wt% NBCPs are found to be −26.9, −24.7, and − 15.8 MeV respectively due to higher electrostatic repulsion and became suitably used for in vivo applications.
... From the stress/strain graph, the tensile strength and % elongation was quantified and subsequently used to compare the films. The maximum tensile strength of a film is the maximum stress that a film can resist being stretched before failing or necking [17]. The tensile strength of the vitamin E/Soluplus V R films at fracture, as a function of vitamin E concentration, is shown in Figure 4. Films made with 0% (neat Soluplus V R ) and 10% vitamin E were brittle. ...
... Increasing the concentration of vitamin E to 20 and 30% caused a significant decline in the tensile strength of the films. This result was consistent with the general expectation for a plasticized polymeric film [17,18]. ...
... Percent elongation is another useful parameter for assessing the plasticizing effect of vitamin E where elongation should increase with increasing plasticizer concentration [17]. As shown in Figure 5, the percent elongation of the vitamin E/Soluplus V R films increased with an increase in vitamin E concentration in the blend from almost negligible elongation for the neat Soluplus V R film to nearly 360% for films made with 30% vitamin E. A significant increase in elongation was particularly evident when the % vitamin E in the films was ! ...
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Objective The goals of this study were to (1) delineate a technique to prepare stable aqueous vitamin E/Soluplus® dispersions; (2) characterize films cast from the aqueous dispersions; and (3) demonstrate the utility of the aqueous dispersions in fluid bed coating applications Significance: This study demonstrated the feasibility of using vitamin E in the preparation of amphiphilic film withs potential use in delayed release coating applications. Methods Low viscosity aqueous vitamin E/Soluplus® dispersions were prepared by first spray drying ethanolic vitamin E/Soluplus® solutions followed by high-shear homogenization of the solid dispersions in water. Concentrated (10%) aqueous dispersions containing 0%, 10%, 20%, and 30% of vitamin E in the binary blend with Soluplus® were then cast into films and characterized for contact angle and mechanical strength by texture analysis. Results All films were hydrophilic and homogenous, which confirmed the utility of vitamin E as a plasticizer for the Soluplus® polymer. The 0% and 10% films were brittle whereas the 30% was tacky. The 20% dispersion was subsequently used to coat acetaminophen granules by a fluidized bed process to a dry weight gain of 10-30%. When tested by a dissolution study, a delay in acetaminophen release was observed as a function of weight gain. Conclusion The results from this study demonstrated that it is feasible to produce stable vitamin E/Soluplus® aqueous dispersions to be used as solvent-free functional film coating materials.