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251.
To reduce cost and increase environmental friendliness, waterborne polyurethane (WPU) is a tempting choice in the field of green chemistry. Biodegradable WPU was synthesized using lysine as an internal emulsifier. WPU was further modified using methylate methacrylate (MMA) as an acrylic monomer. Unsaturated pre-PU was synthesized by using unsaturated end-capping agent 2-hydroxyethyl methacrylate and further extended by MMA to form acrylate modified WPU. A permanent covalent linkage was established between WPU and PMMA as confirmed by FTIR spectroscopy. The focus of this research work was to study the dependence of drug delivery, mechanical, thermal, surface, and structural properties of WPU, on the MMA repeating unit content (10%–40%). For drug release studies mitomycin c was taken as a model anticancer drug. Furthermore, these materials were subjected to in vitro and in vivo cytotoxicity evaluation, which shows that synthesized acrylate modified WPU are biocompatible. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47253. 相似文献
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Gao Wei Iqbal Javed Hu Ruilin 《Bulletin of Engineering Geology and the Environment》2021,80(8):6263-6274
Bulletin of Engineering Geology and the Environment - Soil-rock mixture (S-RM) exerts a major control on slope stability. Baidian County in southeastern China was selected as a case study to better... 相似文献
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Ch M. Munawwar Iqbal Riaz M. Mohsin Iltaf Naima Ghafoor Abdul Ali Syed Sohaib 《Multimedia Tools and Applications》2020,79(19-20):12817-12828
Multimedia Tools and Applications - It is often difficult and essential to distinguish between focused and de-focused structures in an image. To properly handle such structures, an image fusion... 相似文献
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Middya Asif Iqbal Roy Sarbani Dutta Joy Das Rituparna 《Mobile Networks and Applications》2020,25(4):1249-1274
Mobile Networks and Applications - Participatory sensing has become an effective way of sensing urban dynamics due to the widespread availability of smartphones among citizens. Traditionally,... 相似文献
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Nadia Akram Khalid Mahmood Zia Muhammad Saeed Muhammad Usman Shahzad Zafar Iqbal Amina Shafi Waheed Gul Khan 《应用聚合物科学杂志》2020,137(13):48493
The diverse and ubiquitous consumption of polymers urges the necessity to make these materials easily available. However, the excessively used petrochemical-based polymers such as poly(vinyl) chloride (PVC) are nonbiodegradable, which is a motivation to modify it with “green” alternatives. In the present study, PVC (Mw = 48 000 g mol−1) has been incorporated with cornstarch (CS) to synthesize a series of 25 samples of bioplastics in addition to blank polymer samples. The films of five various thicknesses (0.1, 0.2, 0.3, 0.5, and 1.0 mm) have been synthesized using in situ polymerization. Each sample of pure PVC film and bioplastic has been induced with different concentrations of CS in the range of 1–5 wt %. The synthesized samples were subjected to the structural characterization by using Fourier transform infrared. Thermogravimetric analysis has demonstrated the three-step degradation with the improved stability of 250 °C. The 3% concentration of CS has shown the optimum storage modulus (E′) of 1 660 MPa from dynamic mechanical analysis and Tan δ as 0.50. The swelling test performed using water has shown an induction of hydrophilicity in PVC up to 4%. CS-induced bioplastics can be a potential ecofriendly alternative of conventional polymers. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48493. 相似文献
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N. H. Shah W. Phuapradit M. Bachynsky M. H. Infeld K. Iqbal A. W. Malick 《Drug development and industrial pharmacy》1994,20(5):873-888
Bioavailability of a sparingly soluble drug is often limited by the rate of dissolution of the drug substance. The drug in a micronized form is generally employed to maximize the bioavailability. However, the micronized drugs tend to agglomerates and do not always exhibit an improved dissolution rate. In this study, a simple processing using a high energy mill was demonstrated as an effective means to utilize the entire surface area available for drug release of the micronized drug. An experimental hydrophobic drug in a micronized form was milled with a carrier, hydrous lactose using Micropulverizer to achieve a uniform mixture so-called “high energy ordered mixture”. The high energy ordered mixture provided a contact surface area taking part in dissolution 4-fold greater than the micronized drug agglomerates. Therefore, the dissolution was significantly improved, irrespective of test parameters such as agitation and the presence of surfactant. This high energy ordered mixture provided the advantages over a simple ordered mixture for: (i) complete deaggregation of the micronized drug to fine primary particles, (ii) improving the efficiency of the carrier by increasing contact surface area, and (iii) enhancing the bonding effect between the drug and lactose particles due to free water molecules released from the crystal lattices of hydrous lactose during milling. This procedure could be applied to overcome dissolution problems of sparingly soluble drugs with cohesive nature. 相似文献
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