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In this article, the rheological behavior of polyvinyl chloride (PVC)-grafting- diallyl phthalate (DAP) was evaluated with melt flow index measurement and the small amplitude frequency sweep experiments. Frequency sweep tests using a parallel plate rheometer were conducted at 190[degrees]C to evaluate the rheological properties of PVC-g-DAP copolymers with different grafting ratios of DAP (0, 3, 5, 8, and 10%). Frequency sweep data were analyzed in terms of Cole-Cole plot, Han plot, and VGP plot. The results suggested that grafting DAP onto PVC reduced the viscosity and melt elasticity and greatly improved processability of the polymer. The mechanism of the grafting was interpreted as its benefits to promote fusion and gelation level of PVC, which was further confirmed through the SEM study. KEYWORDS grafting, PVC-g-DAP, process property, rheological property, 1 | INTRODUCTION Polyvinyl chloride (PVC), the second largest universal plastic in the world, is an interesting material that has high strength, high modulus, high corrosion resistance, and unique self-extinguish. [...]

Hybrid organic–inorganic formate perovskites, AB(HCOO)3, are a large family of compounds that exhibit a variety of phase transitions and diverse properties, such as (anti)ferroelectricity, ferroelasticity, (anti)ferromagnetism, and multiferroism. While many properties of these materials have already been characterized, we are not aware of any study that focuses on the comprehensive property assessment of a large number of formate perovskites. A comparison of the properties of materials within the family is challenging due to systematic errors attributed to different techniques or the lack of data. For example, complete piezoelectric, dielectric, and elastic tensors are not available. In this work, we utilize first-principles density functional theory based simulations to overcome these challenges and to report structural, mechanical, dielectric, piezoelectric, and ferroelectric properties of 29 formate perovskites. We find that these materials exhibit elastic stiffness in the range 0.5–127.0 GPa; highly anisotropic linear compressibility, including zero and even negative values; dielectric constants in the range 0.1–102.1; highly anisotropic piezoelectric response with the longitudinal values in the range 1.18–21.12 pC/N; and spontaneous polarizations in the range 0.2–7.8 μC/cm2. Furthermore, we propose and computationally characterize a few formate perovskites that have not been reported yet. [ABSTRACT FROM AUTHOR]

Coenzyme Q10 (CoQ10) supplementation appears to be associated with a lower blood pressure. Nevertheless, it remains unclear whether food-sourced CoQ10 will affect new-onset hypertension in general adults. This study investigated the relationship between dietary CoQ10 intake and new-onset hypertension among the general population. Participants without hypertension at baseline from the China Health and Nutrition Survey (CHNS) prospective cohort study were included (n = 11,428). Dietary CoQ10 intake was collected by validated dietary recalls and the food weighing method. Linear and non-linear relationships between dietary CoQ10 intake and new-onset hypertension were analyzed using multivariable Cox proportional hazards models and restricted cubic splines. During follow-up (median: 6 years), 4006 new-onset hypertension cases were documented. Compared with non-consumers, the hazard ratio (HR) and 95% confidence interval (CI) from quintile 2 to 4 total dietary CoQ10 were 0.83 (0.76, 0.91), 0.86 (0.78, 0.94) and 1.01 (0.92, 1.11); total plant-derived CoQ10 were 0.80 (0.73, 0.88), 1.00 (0.91, 1.09) and 1.10 (1.00, 1.20); and animal-derived CoQ10 were 0.65 (0.59, 0.71), 0.58 (0.53, 0.64) and 0.68 (0.62, 0.75). The lowest risk was found at moderate intake, with a non-linear relationship (P nonlinearity < 0.05). Furthermore, the overall inverse association was stronger among individuals without alcohol consumption or eating a low-fat diet. Moderate long-term dietary CoQ10 intake might be protective against new-onset hypertension. However, it follows a non-linear relationship and excessive intake may increase the risk of new-onset hypertension in the Chinese population. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Duration‐tunable afterglow materials have garnered considerable attention in various applications. Herein, carbon dots (CDs)‐based long persistent luminescence (LPL) composites with a tunable duration in an ultrawide range of seconds‐to‐hours levels were designed and prepared for the first time. In contrast to the established CD‐based afterglow materials, we reported that CD‐based composites exhibit LPL in the form of exciplexes and long‐lived charge‐separated states, enabling the LPL to be prolonged from several seconds to over one hour, exceeding the typical regulation range (limited to 1 min). Further studies revealed that the relationship between the excited and charge‐transfer states of CDs plays a pivotal role in activating the LPL and regulating its duration. Furthermore, these composites exhibited high photoluminescence (PL) quantum yields of up to 60.63%, and their LPL was robust under ambient conditions, even in aqueous media. Their robust and superior LPL performance endows these composites with a strong competitive advantage in dynamic display systems, such as tags for time‐resolved data encryption and displays of the remaining time of takeaways. This study offers an approach to preparing CDs‐based LPL composites with tunable durations and may provide new insights for the development of rare‐earth‐free LPL materials. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Duration‐tunable afterglow materials have garnered considerable attention in various applications. Herein, carbon dots (CDs)‐based long persistent luminescence (LPL) composites with a tunable duration in an ultrawide range of seconds‐to‐hours levels were designed and prepared for the first time. In contrast to the established CD‐based afterglow materials, we reported that CD‐based composites exhibit LPL in the form of exciplexes and long‐lived charge‐separated states, enabling the LPL to be prolonged from several seconds to over one hour, exceeding the typical regulation range (limited to 1 min). Further studies revealed that the relationship between the excited and charge‐transfer states of CDs plays a pivotal role in activating the LPL and regulating its duration. Furthermore, these composites exhibited high photoluminescence (PL) quantum yields of up to 60.63%, and their LPL was robust under ambient conditions, even in aqueous media. Their robust and superior LPL performance endows these composites with a strong competitive advantage in dynamic display systems, such as tags for time‐resolved data encryption and displays of the remaining time of takeaways. This study offers an approach to preparing CDs‐based LPL composites with tunable durations and may provide new insights for the development of rare‐earth‐free LPL materials. [ABSTRACT FROM AUTHOR]

Dispersible and functionalizable long persistent luminescent (LPL) materials are highly desired for flexible use of LPL in various fields. However, synthesizing metal‐free LPL systems with stable long‐lived intermediates and reactive surface groups, which are key requirements for robust LPL and the ability to be functionalized, has proven to be challenging. Herein, the microwave‐assisted preparation of carbon dots (CDs)‐based LPL materials is demonstrated with abundant surface amino groups via in situ embedding of CDs into carbon nitrides (CNs). The incorporation of CDs leads to the formation of deep traps and promotes exciton transmission between CDs and trap states, contributing to the generation of LPL. By varying the embedded CDs, tunable LPL ranging from blue to yellow can be achieved, with a duration exceeding 10 min. Due to the covalent bonding between CDs and CNs, the materials (named CDs@CNs) exhibit robust LPL under ambient conditions and evenly dispersed in water through ultrasonic treatment. Furthermore, the surface amino groups serve as sites for further modification, allowing for on‐demand performance design and control, such as adjustable hydrophilicity–hydrophobicity for various applications. This work provides new insights into designing superior flexible CDs‐based LPL materials and expanding the domain of metal‐free LPL materials. [ABSTRACT FROM AUTHOR]