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International Journal of Molecular... Jul 2022In this paper, the synthesis, characterization, and properties of crosslinked poly(ε-caprolactone)-based polyurethanes as potential tissue replacement materials are...
In this paper, the synthesis, characterization, and properties of crosslinked poly(ε-caprolactone)-based polyurethanes as potential tissue replacement materials are reported. The polyurethane prepolymers were prepared from poly(ε-caprolactone)diol (PCD), polyethylene glycol (PEG)/polylactic acid diol (PLAD), and 1,6-hexamethylene diisocyanate (HDI). In these segmented polyurethanes, the role of PEG/PLAD was to tune the hydrophobic/hydrophilic character of the resulting polymer while sucrose served as a crosslinking agent. PLAD was synthesized by the polycondensation reaction of D,L-lactic acid and investigated by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and nuclear magnetic resonance spectroscopy (NMR). The crosslinked polyurethane samples (SUPURs) obtained were characterized by attenuated total reflectance Fourier-transform infrared spectroscopy (AT-FT-IR), swelling, and mechanical (uniaxial tensile tests) experiments. The thermo and thermomechanical behavior were studied by differential scanning calorimetry (DSC) and dynamical mechanical analysis (DMA). The viability of dental pulp stem cells was investigated in the case of polyurethanes composed of fully biocompatible elements. In our studies, none of our polymers showed toxicity to stem cells (DPSCs).
Topics: Biocompatible Materials; Polyesters; Polyethylene Glycols; Polymers; Polyurethanes; Spectroscopy, Fourier Transform Infrared; Sucrose
PubMed: 35887250
DOI: 10.3390/ijms23147904 -
ANZ Journal of Surgery Sep 2021The NovoSorb® Biodegradable Temporising Matrix (BTM) is a synthetic polyurethane dermal matrix used to reconstruct complex wounds including deep dermal and...
BACKGROUND
The NovoSorb® Biodegradable Temporising Matrix (BTM) is a synthetic polyurethane dermal matrix used to reconstruct complex wounds including deep dermal and full-thickness burns, necrotising fasciitis and free flap donor site. We hope to further explore its potential applications in this series.
METHODS
Patients who received BTM application across four centres over an 18-month period were included. Patients were followed up to assess BTM and graft take, the aesthetic, the return of sensation and complications.
RESULTS
A total of 27 patients with 35 wounds were identified with a range of aetiologies. Thirty-three wounds had 100% integration of BTM at the time of sealing membrane removal. Seven wounds had partial graft loss that later healed by secondary intention. In two cases, re-epithelialisation occurred with BTM alone without split-skin graft.
CONCLUSION
BTM offers a safe and reliable reconstructive option in challenging wounds that would otherwise require more complex operations.
Topics: Burns; Humans; Polyurethanes; Plastic Surgery Procedures; Skin Transplantation; Wound Healing
PubMed: 34085755
DOI: 10.1111/ans.16936 -
Annals of Anatomy = Anatomischer... Jan 2022Vascular casting is a widely used method for the representation of body vascularization. Many different injection materials have been described throughout the time to...
Vascular casting is a widely used method for the representation of body vascularization. Many different injection materials have been described throughout the time to enhance the arterial vascular supply within a specifically defined anatomical location. The use of industrial polyurethane has been recently evaluated and applied to animal and human anatomy. The aim of this study was to confirm the safe and reliable use of industrial polyurethane in knee specimen in order to obtain a three-dimensional vascular tree of the distal femur. 10 fresh-frozen knees (mid-thigh to mid tibia) were used to assess the vascularity around the femoral condyles. Industrial polyurethane foam (Soudal™ foam) was diluted with acetone in order to obtain a runny fluid, easy to inject. After injection, the knees were bathed in a 10% NaOH solution, heated at 30°. The corrosion process took from 20 to 24h and allowed all the soft tissue surrounding the knee to be subsided, leaving only the bone with polyurethane vascular architecture. After soft tissue corrosion, the vascular network around the knees was easily identified underlying the relation of the vessels to the bone. Even small arterioles (diameter<1mm) were distinguished with a good resistance to breakage. Corrosion casting remains an easy and reliable alternative to dissection for the understanding of tissue perfusion as the handling of the polyurethane is easy and has low costs. The described author's method can be used osteo-articular specimen as well as in other organs. The protocol of injection and corrosion needs however to be adapted to the different specimen and anatomical location. Polyurethane associated to acetone can safely be used as injection material in order to demonstrate the vascularity of a specimen and remains easy to use.
Topics: Animals; Corrosion Casting; Femur; Humans; Knee; Knee Joint; Polyurethanes
PubMed: 34391913
DOI: 10.1016/j.aanat.2021.151816 -
Scientific Reports Jun 2023Despite meloxicam's many benefits, it will cause many drawbacks if the meloxicam release rate is not controlled. Accordingly, we introduced a technique based on the...
Despite meloxicam's many benefits, it will cause many drawbacks if the meloxicam release rate is not controlled. Accordingly, we introduced a technique based on the electrospinning process to control the release rate and also to reduce side effects. For this purpose, different nanofibers were used as drug couriers. Nanofibers were prepared using polyurethane, polyethylene glycol, and light curable poly (ethylene glycol) diacrylate (PEGDA) by electrospinning. In fact, light curable poly (ethylene glycol) diacrylate (PEGDA) was synthesized as a hydrophilic functional group. Next, PEGDA and polyurethane were used simultaneously to fabricate the drug carrier nanofiber in a single processing step, and the electrospinning apparatus was equipped with a blue light source for in-situ photopolymerization during the electrospinning process. The molecular structures of nanofibers and PEGDA were investigated by FT-IR, H NMR, C NMR, SEM, TEM, XRD, and DSC analyses. Finally, we reduced in vitro drug release to 44% within ten hours, while the minimum release of meloxicam from the tablet was 98%.
Topics: Nanofibers; Meloxicam; Polyurethanes; Spectroscopy, Fourier Transform Infrared; Polyethylene Glycols; Drug Carriers
PubMed: 37328688
DOI: 10.1038/s41598-023-36893-9 -
Environmental Science & Technology Dec 2022The release of fragments from plastic products, that is, secondary microplastics, is a major concern in the context of the global plastic pollution. Currently available...
The release of fragments from plastic products, that is, secondary microplastics, is a major concern in the context of the global plastic pollution. Currently available (thermoplastic) polyurethanes [(T)PU] are not biodegradable and therefore should be recycled. However, the ester bond in (T)PUs might be sufficiently hydrolysable to enable at least partial biodegradation of polyurethane particles. Here, we investigated biodegradation in compost of different types of (T)PU to gain insights into their fragmentation and biodegradation mechanisms. The studied (T)PUs varied regarding the chemistry of their polymer backbone (aromatic/aliphatic), hard phase content, cross-linking degree, and presence of a hydrolysis-stabilizing additive. We developed and validated an efficient and non-destructive polymer particle extraction process for partially biodegraded (T)PUs based on ultrasonication and density separation. Our results showed that biodegradation rates and extents decreased with increasing cross-linking density and hard-segment content. We found that the presence of a hydrolysis stabilizer reduced (T)PU fragmentation while not affecting the conversion of (T)PU carbon into CO. We propose a biodegradation mechanism for (T)PUs that includes both mother particle shrinkage by surface erosion and fragmentation. The presented results help to understand structure-degradation relationships of (T)PUs and support recycling strategies.
Topics: Humans; Polyurethanes; Plastics; Microplastics; Polymers; Biodegradation, Environmental; Suppuration
PubMed: 36394826
DOI: 10.1021/acs.est.2c05602 -
International Journal of Molecular... Jun 2021Segmented polyurethane ionomers find prominent applications in the biomedical field since they can combine the good mechanical and biostability properties of...
Segmented polyurethane ionomers find prominent applications in the biomedical field since they can combine the good mechanical and biostability properties of polyurethanes (PUs) with the strong hydrophilicity features of ionomers. In this work, PU ionomers were prepared from a carboxylated diol, poly(tetrahydrofuran) (soft phase) and a small library of diisocyanates (hard phase), either aliphatic or aromatic. The synthesized PUs were characterized to investigate the effect of ionic groups and the nature of diisocyanate upon the structure-property relationship. Results showed how the polymer / phase segregation was affected by both the concentration of ionic groups and the type of diisocyanate. Specifically, PUs obtained with aliphatic diisocyanates possessed a / phase segregation stronger than PUs with aromatic diisocyanates, as well as greater bulk and surface hydrophilicity. In contrast, a higher content of ionic groups per polymer repeat unit promoted phase mixing. The neutralization of polymer ionic groups with silver or zinc further increased the / phase segregation and provided polymers with antimicrobial properties. In particular, the Zinc/PU hybrid systems possessed activity only against the Gram-positive while Silver/PU systems were active also against the Gram-negative . The herein-obtained polyurethanes could find promising applications as antimicrobial coatings for different kinds of surfaces including medical devices, fabric for wound dressings and other textiles.
Topics: Biocompatible Materials; Materials Testing; Phase Transition; Polyurethanes; Pseudomonas aeruginosa; Silver; Staphylococcus epidermidis; Tensile Strength; Zinc
PubMed: 34200185
DOI: 10.3390/ijms22116134 -
International Journal of Molecular... Feb 2023Vibration and noise-reduction materials are indispensable in various fields. Polyurethane (PU)-based damping materials can dissipate the external mechanical and acoustic...
Vibration and noise-reduction materials are indispensable in various fields. Polyurethane (PU)-based damping materials can dissipate the external mechanical and acoustic energy through molecular chain movements to mitigate the adverse effects of vibrations and noise. In this study, PU-based damping composites were obtained by compositing PU rubber prepared using 3-methyltetrahydrofuran/tetrahydrofuran copolyether glycol, 4,4'-diphenylmethane diisocyanate, and trimethylolpropane monoallyl ether as raw materials with hindered phenol, viz., and 3,9-bis{2-[3-(3--butyl-4-hydroxy-5-methylphenyl)proponyloxy]-1,1-dimethylethyl}-2,4,8,10-tetraoxaspiro[5.5]undecane (AO-80). Fourier transform infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry, dynamic mechanical analysis, and tensile tests were conducted to evaluate the properties of the resulting composites. The glass transition temperature of the composite increased from -40 to -23 °C, and the tan of the PU rubber increased by 81%, from 0.86 to 1.56 when 30 phr of AO-80 was added. This study provides a new platform for the design and preparation of damping materials for industrial applications and daily life.
Topics: Elastomers; Polyurethanes; Phenol; Rubber; Phenols
PubMed: 36902089
DOI: 10.3390/ijms24054662 -
Advanced Science (Weinheim,... Jul 2022High-performance flexible pressure sensors have attracted a great deal of attention, owing to its potential applications such as human activity monitoring, man-machine...
High-performance flexible pressure sensors have attracted a great deal of attention, owing to its potential applications such as human activity monitoring, man-machine interaction, and robotics. However, most high-performance flexible pressure sensors are complex and costly to manufacture. These sensors cannot be repaired after external mechanical damage and lack of tactile feedback applications. Herein, a high-performance flexible pressure sensor based on MXene/polyurethane (PU)/interdigital electrodes is fabricated by using a low-cost and universal spray method. The sprayed MXene on the spinosum structure PU and other arbitrary flexible substrates (represented by polyimide and membrane filter) act as the sensitive layer and the interdigital electrodes, respectively. The sensor shows an ultrahigh sensitivity (up to 509.8 kPa ), extremely fast response speed (67.3 ms), recovery speed (44.8 ms), and good stability (10 000 cycles) due to the interaction between the sensitive layer and the interdigital electrodes. In addition, the hydrogen bond of PU endows the device with the self-healing function. The sensor can also be integrated with a circuit, which can realize tactile feedback function. This MXene-based high-performance pressure sensor, along with its designing/fabrication, is expected to be widely used in human activity detection, electronic skin, intelligent robots, and many other aspects.
Topics: Electrodes; Feedback; Humans; Polyurethanes; Pressure; Touch; Wearable Electronic Devices
PubMed: 35460195
DOI: 10.1002/advs.202200507 -
International Journal of Molecular... Feb 2022The purpose of this review article is to outline the extended applications of polyurethane (PU)-based nanocomposites incorporated with conductive polymeric particles as... (Review)
Review
The purpose of this review article is to outline the extended applications of polyurethane (PU)-based nanocomposites incorporated with conductive polymeric particles as well as to condense an outline on the chemistry and fabrication of polyurethanes (PUs). Additionally, we discuss related research trends of PU-based conducting materials for EMI shielding, sensors, coating, films, and foams, in particular those from the past 10 years. PU is generally an electrical insulator and behaves as a dielectric material. The electrical conductivity of PU is imparted by the addition of metal nanoparticles, and increases with the enhancing aspect ratio and ordering in structure, as happens in the case of conducting polymer fibrils or reduced graphene oxide (rGO). Nanocomposites with good electrical conductivity exhibit noticeable changes based on the remarkable electric properties of nanomaterials such as graphene, RGO, and multi-walled carbon nanotubes (MWCNTs). Recently, conducting polymers, including PANI, PPY, PTh, and their derivatives, have been popularly engaged as incorporated fillers into PU substrates. This review also discusses additional challenges and future-oriented perspectives combined with here-and-now practicableness.
Topics: Electric Conductivity; Graphite; Nanocomposites; Nanotubes, Carbon; Polymers; Polyurethanes
PubMed: 35216059
DOI: 10.3390/ijms23041938 -
Medicina (Kaunas, Lithuania) Mar 2024: Nucleotide delivery has emerged as a noteworthy research trend in recent years because of its potential utility in addressing a range of genetic defects resulting in...
: Nucleotide delivery has emerged as a noteworthy research trend in recent years because of its potential utility in addressing a range of genetic defects resulting in the presence of incorrect nucleotides. The primary goals of this research were to create and to characterize polyurethane microstructures, with the aim of utilizing them for nucleotide transport. : Two samples were prepared using an aliphatic diisocyanate in reaction with a mixture of polyethylene glycol and polycaprolactone diol, where 2'-deoxycytidinic acid was used as the active agent and glycerol 1,2-diacetate was used as an enhancer of the aqueous solubility. The solubility, pH, size distribution, and surface charge of the samples were measured, and encapsulation efficacy and release, cell proliferation, and irritation tests on mouse skin were conducted. : The results showed almost neutral acidic-basic structures with a high heterogeneity, and a medium tendency to form clusters with non-cytotoxic and non-irritative potentials. : Future research could explore the efficacy of this carrier in delivering other nucleotides, as well as investigating the long-term effects and safety of these microstructures in vivo.
Topics: Animals; Mice; Drug Carriers; Polyurethanes; Polyethylene Glycols; Solubility; Nucleotides
PubMed: 38541217
DOI: 10.3390/medicina60030491