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1.
SAGE Open Nurs ; 10: 23779608241255300, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38779615

RESUMO

Introduction: Nurses are required to fulfill many roles, including expertise, communication, and leadership and are psychologically vulnerable due to lack of manpower, emotional labor, and shift work. Among them, it is necessary to understand the psychological well-being of new nurses and junior nurses who have a high early resignation rate. Objective: The purpose of this study was to investigate psychological well-being of nurses and compare psychological well-being of nurses from the first to the fifth years of clinical experience. Methods: Cross-sectional comparative design and purposive sampling method were used. Data were collected from 148 nurses with one to five years of experience working in tertiary care general hospitals. On November 11, 2021, an online link for the structured questionnaire was sent to the group social networking service accounts for nurses. Psychological well-being was assessed using a Korean version of the Scales of Psychological Well-being including autonomy, environmental mastery, personal growth, positive relations with others, purpose in life, and self-acceptance. Results: The average psychological well-being of nurses was 194.11, with significant differences depending on years of clinical experience (p = .006, F = 3.82) and satisfaction with nursing (p < .001, F = 13.12). It was lowest at 180.08 in the first year, gradually improving, but falling again from the fourth year. Among five subfactors except positive relations with others (p = .389), psychological well-being was related to clinical experiences years using satisfaction with nursing and religion as covariates. Conclusions: This study that compared psychological well-being from the first to the fifth year according to clinical experience revealed the need for optimized intervention for each year. Nursing managers can improve the psychological well-being of nurses through active and appropriate intervention according to the passage of nursing experience.

2.
Gastroenterology ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38788861

RESUMO

BACKGROUND AND AIMS: CT-P13 subcutaneous (SC), an SC formulation of the intravenous (IV) infliximab biosimilar CT-P13 IV, creates a unique exposure profile. We aimed to demonstrate superiority of CT-P13 SC versus placebo as maintenance therapy in patients with Crohn's disease (CD) and ulcerative colitis (UC). METHODS: Two randomized, placebo-controlled, double-blind studies were conducted in patients with moderately-to-severely active CD or UC and inadequate response/intolerance to corticosteroids and immunomodulators. All patients received open-label CT-P13 IV 5 mg/kg at weeks (W) 0, 2, and 6. At W10, clinical responders were randomized (2:1) to CT-P13 SC 120 mg or placebo every 2 weeks until W54 (maintenance phase) using pre-filled syringes. (Co-)primary endpoints were clinical remission and endoscopic response (CD) and clinical remission (UC) at W54 (all-randomized population). RESULTS: Overall, 396 patients with CD and 548 patients with UC received induction treatment. At W54 in the CD study, statistically significant higher proportions of CT-P13 SC- versus placebo-treated patients achieved clinical remission (62.3% versus 32.1%; P < 0.0001) and endoscopic response (51.1% versus 17.9%; P < 0.0001). In the UC study, clinical remission rates at W54 were statistically significantly higher with CT-P13 SC versus placebo (43.2% versus 20.8%; P < 0.0001). Achievement of key secondary endpoints was significantly higher with CT-P13 SC versus placebo across both studies. CT-P13 SC was well tolerated, with no new safety signals identified. CONCLUSION: CT-P13 SC was more effective than placebo as maintenance therapy and well tolerated in patients with moderately-to-severely active CD or UC who responded to CT-P13 IV induction. CLINICALTRIALS: gov, NCT03945019 (CD) and NCT04205643 (UC).

3.
Asian Bioeth Rev ; 16(2): 267-279, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38586567

RESUMO

The increase of high-risk newborns due to societal changes has presented neonatal intensive care unit nurses with more ethical challenges and heightened their perception of neonatal palliative care. Therefore, this study was a descriptive survey exploring the perceptions of neonatal intensive care unit nurse regarding biomedical ethics and neonatal palliative care in neonatal intensive care units. The research participants were 97 neonatal intensive care unit nurses who had been directly involved with end-of-life care for high-risk babies. Data were collected from November to December 2021 through an online survey. The Korean version of Neonatal Palliative Care Attitude Scale and the tool of biomedical ethics were used. The collected data were analyzed using the T-test, ANOVA, Scheffé test, Pearson correlation coefficient, and multiple regression analysis. The mean score for perception of biomedical ethics in neonatal intensive care unit nurses was 2.89 of 4, and that of neonatal palliative care in neonatal intensive care unit nurses was 3.10 of 5. Existence of a protocol of neonatal palliative care, the experience of patients dying, and the right to life of neonates were factors influencing the perception of neonatal palliative care. The explanatory power was 12.5%. The data support the importance of guidelines regarding systematic neonatal palliative care. Also, developing programs for sharing and supporting experiences of patients dying among colleagues and persistent education about the right to life of neonates for neonatal intensive care unit nurses can improve perception of neonatal palliative care.

4.
J Clin Med ; 13(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38610758

RESUMO

Objectives: Augmented reality (AR) navigation systems are emerging to simplify and enhance the precision of medical procedures. Lumbosacral transforaminal epidural injection is a commonly performed procedure for the treatment and diagnosis of radiculopathy. Accurate needle placement while avoiding critical structures remains a challenge. For this purpose, we conducted a randomized controlled trial for our augmented reality navigation system. Methods: This randomized controlled study involved 28 patients, split between a traditional C-arm guided group (control) and an AR navigation guided group (AR-NAVI), to compare procedure efficiency and radiation exposure. The AR-NAVI group used a real-time tracking system displaying spinal structure and needle position on an AR head-mounted display. The procedural time and C-arm usage (radiation exposure) were measured. Results: All patients underwent successful procedures without complications. The AR-NAVI group demonstrated significantly reduced times and C-arm usage for needle entry to the target point (58.57 ± 33.31 vs. 124.91 ± 41.14, p < 0.001 and 3.79 ± 1.97 vs. 8.86 ± 3.94, p < 0.001). Conclusions: The use of the AR navigation system significantly improved procedure efficiency and safety by reducing time and radiation exposure, suggesting a promising direction for future enhancements and validation.

5.
Polymers (Basel) ; 16(7)2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38611246

RESUMO

Currently, metal is the most common exterior material used in robot development due to the need to protect the motor. However, as soft, wearable, and humanoid robots are gradually being developed, many robot parts need to be converted into artificial skin using flexible materials. In this study, in order to develop soft exterior parts for robots, we intended to manufacture exterior robot arm parts via fused filament fabrication (FFF) 3D printing according to various structural and thickness conditions and analyze their mechanical properties. The exterior parts of the robot arms were manufactured utilizing Shore 95 A TPU (eTPU, Esun, Shenzhen, China), which is renowned for its softness and exceptional shock absorption characteristics. The exterior robot arm parts were modeled in two parts, the forearm and upper arm, by applying solid (SL) and re-entrant (RE) structures and thicknesses of 1, 2, and 4 mm. The mechanical properties were analyzed through the use of three-point bending, tensile, and compression testing. All of the characterizations were analyzed using a universal testing machine (AGS-X, SHIMADZU, Kyoto, Japan). After testing the samples, it was confirmed that the RE structure was easily bendable towards the bending curve and required less stress. In terms of the tensile tests, the results were similar to the bending tests; to achieve the maximum point, less stress was required, and for the compression tests, the RE structure was able to withstand the load compared to the SL structure. Therefore, after analyzing all three thicknesses, it was confirmed that the RE structure with a 2 mm thickness had excellent characteristics in terms of bending, tensile, and compressive properties. Therefore, the re-entrant pattern with a 2 mm thickness is more suitable for manufacturing a 3D-printed humanoid robot arm.

6.
Pharmaceuticals (Basel) ; 17(2)2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38399447

RESUMO

The epidermal growth factor receptor (EGFR), also known as ErbB1 and HER1, belongs to the receptor tyrosine kinase family. EGFR serves as the primary driver in non-small-cell lung cancer (NSCLC) and is a promising therapeutic target for NSCLC. In this study, we synthesized a novel chemical library based on a benzofuran-indole hybrid scaffold and identified 8aa as a potent and selective EGFR inhibitor. Interestingly, 8aa not only showed selective anticancer effects against NSCLC cell lines, PC9, and A549, but it also showed significant inhibitory effects against the double mutant L858R/T790M EGFR, which frequently occurs in NSCLC. In addition, in PC9 and A549 cells, 8aa potently blocked the EGFR signaling pathway, cell viability, and cell migration. These findings suggest that 8aa, a benzofuran-indole hybrid derivative, is a novel EGFR inhibitor that may be a potential candidate for the treatment of NSCLC patients with EGFR mutations.

8.
J Pediatr Nurs ; 76: 38-44, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38359543

RESUMO

PURPOSE: The purpose of this study was to examine the effects of psychological separation and health locus of control on the health care transition readiness of adolescents and young adults (AYAs) with type 1 diabetes. METHODS: Data were collected between December 2020 and October 2021. One hundred twelve AYAs with type 1 diabetes treated at a tertiary hospital and under follow-up observation as well as AYAs with type 1 diabetes nationwide who were part of the type 1 diabetes internet community were enrolled. The Psychological Separation Inventory, the Multidimensional Health Locus of Control scale from C, and the Self-management and Transition to Adulthood with Therapeutics = Rx Questionnaire were used. RESULTS: Multiple regression analysis indicated that age (ß = 0.302, p = .001), hemoglobin A1c (HbA1c) (ß = -0.174, p = .040), conflictual separation (ß = 0.242, p = .005), functional separation (ß = 0.200, p = .045) and attitudinal separation (ß = -0.240 p = .015) were significantly associated with health management transition readiness; these predictors explained 27.6% of health care transition readiness (F = 8.062, p = .000). CONCLUSIONS: AYAs with type 1 diabetes can enhance readiness for health care transition by fostering psychological separation from parents, effectively managing blood glucose levels, and taking into account age-related factors during the preparation process. At this point, it is essential for healthcare professionals to guide parents in recognizing adolescents' psychological independence and facilitating their supportive role through the process of redefining their roles. PRACTICE IMPLICATIONS: Health care providers should promote psychological separation in AYAs. Additionally, taking into account the developmental characteristics of adolescence can facilitate a successful health care transition.


Assuntos
Diabetes Mellitus Tipo 1 , Controle Interno-Externo , Transição para Assistência do Adulto , Humanos , Diabetes Mellitus Tipo 1/psicologia , Diabetes Mellitus Tipo 1/terapia , Adolescente , Masculino , Feminino , Adulto Jovem , Inquéritos e Questionários , Adulto
9.
Heliyon ; 9(11): e22528, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38058643

RESUMO

Purpose: The purpose of this study was to investigate and compare perceived parental empathy between adolescents with and without leukemia. Methods: This study used a cross-sectional, descriptive design. Thirty-eight adolescents with leukemia and 205 without, completed a self-reported questionnaire regarding their perceptions of parental empathy and general characteristics. For this comparative study, adolescents were selected through matched sampling, and 38 adolescents per group were used for analysis. Data were examined using independent t-tests. Results: In terms of parental empathy, excessive emotional reactions and cold emotional reactions were perceived more frequently by adolescents with leukemia than healthy adolescents. Differences between the two groups were statistically significant. Conclusion: Since parents caring for children with leukemia have an extra burden in caring for their children, these parents are continuously anxious about prognoses, and tend to feel guilty for their child's disease. Thus, healthcare providers need to develop a program for improving the ability of parents of cancer patients to demonstrate empathy, focusing on how to recognize and manage what may be perceived by their children as excessive or cold emotional reactions, and must take a role in communicating to parents how adolescents with leukemia perceive parental rearing behaviors and the impacts of these behaviors on their well-being.

10.
Chem Commun (Camb) ; 59(92): 13727-13730, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37909258

RESUMO

We demonstrate that o-closo-(TeMe)2carborane directs, in the presence of linear ditopic neutral Lewis bases, the formation of co-crystals with 1D extended supramolecular networks. Specifically, the network formation is systematically stabilized by short and quasi-linear C-Te⋯N chalcogen-bonding (ChB) interactions. In sum, we report efficient carborane-based tectons to rationally design high-dimensional neutral heteromolecular networks.

11.
Nutrients ; 15(20)2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37892560

RESUMO

Menopause is a significant phase in a woman's life. Menopausal symptoms can affect overall well-being and quality of life. Conventionally, hormone replacement therapy (HRT) is used to alleviate menopausal symptoms; however, depending on the conditions, HRT may lead to side effects, necessitating the exploration of alternative therapies with fewer side effects. In this study, we investigated the effects of a combination of soybean germ extract (S30) containing 30% (w/w) isoflavone and a probiotic, Lactobacillus gasseri (LGA1), on menopausal conditions in an ovariectomized (OVX) rat model. We evaluated the impact of S30+LGA on body weight, estrogen markers, uterine and bone health, vascular markers, and neurotransmitter levels. The results revealed that treatment with S30+LGA1 significantly improved body weight and uterine and bone health. Moreover, S30+LGA1 demonstrated promising effects on lipid profile, liver function, and vascular markers and positively impacted serotonin and norepinephrine levels, indicating potential mood-enhancing effects. In conclusion, S30+LGA1, possessing anti-menopausal effects in vitro and in vivo, can be recommended as a soy-based diet, which offers various health benefits, especially for menopausal women.


Assuntos
Glycine max , Lactobacillus gasseri , Ratos , Animais , Feminino , Humanos , Qualidade de Vida , Menopausa , Extratos Vegetais/farmacologia , Peso Corporal
12.
Sci Rep ; 13(1): 17728, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37853073

RESUMO

In this study, to develop soft pressure sensor applicable to wearable robots using stretchable polymers and conductive fillers, 3.25 wt% carbon nanotubes/thermoplastic polyurethane filament with shore 94 A were manufactured. Three infill densities (20%, 50%, and 80%) and patterns (zigzag (ZG), triangle (TR), honeycomb (HN)) were applied to print cubes via fused filament fabrication 3D printing. Most suitable infill conditions were confirmed based on the slicing images, morphologies, compressive properties, electrical properties, and electrical heating properties. For each infill pattern, ZG and TR divided the layers into lines and figures, and the layers were stacked by rotation. For HN, the same layers were stacked in a hexagonal pattern. Consequently, TR divided layer in various directions, showed the strongest compressive properties with toughness 1.99 J for of infill density 80%. Especially, the HN became tougher with increased infill density. Also, the HN laminated with the same layer showed excellent electrical properties, with results greater than 14.7 mA. The electrical heating properties confirmed that ZG and HN had the high layer density, which exhibited excellent heating characteristics. Therefore, it was confirmed that performance varies depending on the 3D printing direction, and it was confirmed that HN is suitable for manufacturing soft sensors.

13.
J Clin Med ; 12(18)2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37762980

RESUMO

Knee osteoarthritis (KOA) is a prevalent common cause of disability and pain among adults. Transcutaneous radiofrequency (RF) diathermy and therapeutic ultrasound (US) are commonly employed treatments for addressing musculoskeletal conditions. This study aims to evaluate and compare the clinical effectiveness of transcutaneous 4.4 MHz RF diathermy and therapeutic US therapy in individuals diagnosed with KOA. A total of 108 patients with KOA were randomly assigned to either the RF or US groups. Each participant underwent a series of 10 treatment sessions over four weeks and was evaluated at different time points. The assessments included physical evaluations, vital sign measurements, the Numeric Rating Scale (NRS) for pain, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores, the Lequesne index, gait analysis, the 36-Item Short Form Health Survey (SF-36), and analysis of adverse responses. Both groups showed significant differences in NRS, WOMAC scores, and Lequesne index compared to baseline values at both the 10th treatment session and the one-month follow-up assessment. However, no significant disparities were observed between the two groups at each assessment point. In the gait analysis, following the 10th treatment, the RF group showed significant changes in stride length and stride velocity compared to baseline. Four weeks after the completion of treatment, both groups exhibited significant alterations in stride length and stride velocity when compared to baseline measurements. However, regarding cadence, only the RF group exhibited a significant difference compared to baseline. The findings suggest that transcutaneous 4.4 MHz RF diathermy displays a comparable effectiveness to therapeutic US in reducing pain and enhancing functional capacity among individuals with KOA. Further research endeavors are warranted to advance the efficacy of noninvasive treatments for KOA.

14.
Child Health Nurs Res ; 29(3): 229-236, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37554090

RESUMO

PURPOSE: The purpose of this study was to investigate perceptions of fatherhood among fathers of high-risk neonates and their confidence regarding neonatal care. METHODS: A study was conducted of 100 fathers whose neonates had been admitted to a neonatal intensive care unit (NICU) for at least 48 hours. Perceptions of fatherhood, neonatal characteristics, and fathers' confidence regarding neonatal care were measured using a self-reported questionnaire. The survey took approximately 10 minutes to complete and was completed anonymously. The factors that affected fathers' confidence regarding neonatal care were analyzed using multiple regression. RESULTS: The scores for positive and negative perceptions of fatherhood were relatively high at 4.27 and 3.42 out of 5 points, respectively. A positive perception of fatherhood was found to influence fathers' confidence regarding neonatal care. CONCLUSION: NICU nurses should encourage fathers to effectively perform their parenting roles by implementing educational programs and interventions to promote positive perceptions of fatherhood and fathers' confidence regarding neonatal care after discharge.

15.
ACS Chem Neurosci ; 14(17): 3025-3034, 2023 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-37552840

RESUMO

Abnormal assembly of amyloid ß (Aß) in the brain is implicated in Alzheimer's disease (AD) and is associated with cognitive impairments. Since Aß accumulation occurs in advance of the onset of clinical symptoms, identifying preventable drug candidates regulating Aß accumulation is regarded as a promising approach in AD therapeutic. Herein, we synthesized eight Yonsei Institute of pharmaceutical sciences Alzheimer's Drug (YIAD) compounds based on 5-benzyl-6-phenylbenzo[4,5]imidazo[1,2-a]pyrrolo[2,1-c]pyrazine structures. Subsequently, YIAD-0203 and YIAD-0205 were selected as effective candidates via thioflavin T assays and gel electrophoresis. The potential therapeutic effect of YIAD-0203 and YIAD-0205 on Aß aggregates was investigated through an AD transgenic mouse model with five familial AD mutations (5XFAD) by oral gavage. Significant amounts of Aß plaque and oligomer reduction were observed in the hippocampus region of both 4.3-month-old (early stage of AD) and 6.0-month-old (mid stage of AD) YIAD-0205-treated 5XFAD mice brains when compared to the nontreated brains. The ability of YIAD-0205 to ameliorate Aß aggregates in the early and mid stages of AD progression supports the notion that YIAD-0205 could be utilized as a reliable scaffold for the development of preventive AD drug candidates.


Assuntos
Doença de Alzheimer , Camundongos , Animais , Camundongos Transgênicos , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Amiloide , Imidazóis , Modelos Animais de Doenças , Placa Amiloide , Precursor de Proteína beta-Amiloide/metabolismo
16.
Cell ; 186(16): 3476-3498.e35, 2023 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-37541199

RESUMO

To improve the understanding of chemo-refractory high-grade serous ovarian cancers (HGSOCs), we characterized the proteogenomic landscape of 242 (refractory and sensitive) HGSOCs, representing one discovery and two validation cohorts across two biospecimen types (formalin-fixed paraffin-embedded and frozen). We identified a 64-protein signature that predicts with high specificity a subset of HGSOCs refractory to initial platinum-based therapy and is validated in two independent patient cohorts. We detected significant association between lack of Ch17 loss of heterozygosity (LOH) and chemo-refractoriness. Based on pathway protein expression, we identified 5 clusters of HGSOC, which validated across two independent patient cohorts and patient-derived xenograft (PDX) models. These clusters may represent different mechanisms of refractoriness and implicate putative therapeutic vulnerabilities.


Assuntos
Cistadenocarcinoma Seroso , Neoplasias Ovarianas , Proteogenômica , Feminino , Humanos , Cistadenocarcinoma Seroso/tratamento farmacológico , Cistadenocarcinoma Seroso/genética , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética
17.
Mar Drugs ; 21(6)2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37367665

RESUMO

Agarobiose (AB; d-galactose-ß-1,4-AHG), produced by one-step acid hydrolysis of agarose of red seaweed, is considered a promising cosmetic ingredient due to its skin-moisturizing activity. In this study, the use of AB as a cosmetic ingredient was found to be hampered due to its instability at high temperature and alkaline pH. Therefore, to increase the chemical stability of AB, we devised a novel process to synthesize ethyl-agarobioside (ethyl-AB) from the acid-catalyzed alcoholysis of agarose. This process mimics the generation of ethyl α-glucoside and glyceryl α-glucoside by alcoholysis in the presence of ethanol and glycerol during the traditional Japanese sake-brewing process. Ethyl-AB also showed in vitro skin-moisturizing activity similar to that of AB, but showed higher thermal and pH stability than AB. This is the first report of ethyl-AB, a novel compound produced from red seaweed, as a functional cosmetic ingredient with high chemical stability.


Assuntos
Bebidas Alcoólicas , Alga Marinha , Sefarose/química , Fermentação , Alga Marinha/química , Glucosídeos
18.
Org Biomol Chem ; 21(18): 3881-3895, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37097478

RESUMO

Herein we describe the divergent synthesis of two types of indolizines via construction of the pyrrole moiety from pyridine-2-acetonitriles, arylglyoxals, and TMSCN. While one-pot three-component coupling provided 2-aryl-3-aminoindolizines via an unusual fragmentation process, a sequential two-step assembly protocol with these starting materials allowed efficient access to a wide range of new 2-acyl-3-aminoindolizines through an aldol condensation-Michael addition-cycloisomerization process. The subsequent manipulation of 2-acyl-3-aminoindolizines enabled direct access to novel polycyclic N-fused heteroaromatic skeletons.

19.
Polymers (Basel) ; 15(6)2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36987207

RESUMO

This study purposed to develop conductivity 3D printed (3DP) fingertips and confirm their potential for use in a pressure sensor. Index fingertips were 3D printed using thermoplastic polyurethane filament with three types of infill patterns (Zigzag (ZG), Triangles (TR), Honeycomb (HN)) and densities (20%, 50%, 80%). Hence, the 3DP index fingertip was dip-coated with 8 wt% graphene/waterborne polyurethane composite solution. The coated 3DP index fingertips were analyzed by appearance property, weight changes, compressive property, and electrical property. As results, the weight increased from 1.8 g to 2.9 g as infill density increased. By infill pattern, ZG was the largest, and the pick-up rate decreased from 18.9% for 20% infill density to 4.5% for 80% infill density. Compressive properties were confirmed. Compressive strength increased as infill density increased. In addition, the compressive strength after coating was improved more than 1000 times. Especially, TR had excellent compressive toughness as 13.9 J for 20%, 17.2 J for 50%, and 27.9 J for 80%. In the case of electrical properties, the current become excellent at 20% infill density. By infill patterns at 20% infill density, TR has 0.22 mA as the best conductivity. Therefore, we confirmed the conductivity of 3DP fingertips, and the infill pattern of TR at 20% was most suitable.

20.
Polymers (Basel) ; 15(6)2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36987323

RESUMO

The development of waterborne polyurethane (WPU) has been stimulated as an alternative to solvent-based polyurethanes due to low-VOC alternatives and reduced exposure to solvents. However, their relatively low mechanical performance and degradation have presented challenges in their wide application. Here, we developed environmentally-friendly bio polyol-based WPU nanocomposite dispersions and films, and presented the optimal process conditions for their manufacture. Additionally, the condition was established without using harmful catalysts or ethyl methyl ketone (MEK) during the polymerization. Moreover, regenerated cellulose nanoparticles (RCNs) were employed as natural chain-extenders in order to improve the biodegradability and mechanical performances of the nanocomposite films. The RCNs have a lower crystallinity compared to cellulose nanocrystals (CNCs), allowing them to possess high toughness without interfering with the elastomeric properties of polyurethane. The prepared CWPU/RCNs nanocomposite films exhibited high toughness of 58.8 ± 3 kgf∙mm and elongation at break of 240 ± 20%. In addition, depending on the molar ratio of NCO/OH, the polyurethane particle size is variously controlled from 70 to 230 nm, enabling to fabricate their dispersions with various transmittances. We believe that our findings not only open a meaningful path toward green elastomers with biodegradability but provides the design concept for bio-elastomers in order to develop industrial elastomers with mechanical and thermal properties.

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