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The biodegradable materials cannot meet the requirements as the agricultural film due to the poor UV resistance and antidripping performance. The work herein thus presented the development of the green‐based anti‐ultraviolet and antidripping multifunctional composite films using poly(butyleneadipate‐co‐terephthalate), microfibrillated cellulose (MFC), and soybean protein isolate (SPI) as the raw materials in the presence of other agents. The resulting composite films were systematically characterized using scanning electron microscope, thermogravimetry analysis (TG), UV, and rheometer measurements. The morphology changed obviously after introducing the MFC and SPI into the substrate film. In addition, the results indicated that the addition of MFC and SPI had a positive effect on the thermal stability and heat preservation of the film, respectively. The contact angle results indicated that SPI was an ideal antidripping agent and the MFC could be used as the release agent. The time of the first water drop of the film containing 2.5 g MFC and 2.0 g SPI was 6 min and 46 s, and the time of each 10 drops was less than 60 s, showing the advantages of using MFC as the release agent and SPI as the antidripping agent. The resulting multifunctional biodegradable films can be widely used in the agricultural and packaging fields. [ABSTRACT FROM AUTHOR]

Mica is a variety of filler material with excellent barrier properties. In the present study, mica‐AKD was successfully prepared by treating sericite mica surface with alkyl ketene dimer (AKD). The distribution and content of AKD in mica, the mode of its binding with mica and its surface properties were characterized by thermogravimetry, Soxhlet extraction, Fourier infrared analysis, the scanning electron microscope with energy spectrum and contact angle analysis. The results show that AKD was combined with mica through physical adsorption and chemical grafting, with the content of AKD in mica‐AKD exceeding 5 wt%. Due to AKD‐coated mica surface, mica‐AKD showed hydrophobicity. PCM and PCMa films were prepared by blending PBAT and PPC with mica and mica‐AKD, respectively. Given the same content, mica‐AKD has better compatibility with PBAT/PPC matrix, and PCMa films show better mechanical properties, lower water vapor permeability and oxygen permeability, and higher CDTR/OTR ratio, which has a good application prospect in fruit and vegetable preservation materials. [ABSTRACT FROM AUTHOR]

The gas barrier properties of poly(butylene adipate‐co‐terephthalate) (PBAT) films can be improved with poly(propylene carbonate) (PPC), but this will reduce the mechanical properties. In this work, PBAT/PPC composites and the related films were prepared by melt blending followed by film blowing process using triglycidyl isocyanurate (TGIC) as the reactive compatibilizer. Herein, the structure, thermal properties, mechanical properties, and gas barrier properties of the composites were systematically characterized via various techniques. The results indicated that the incorporation of TGIC effectively improved the interfacial compatibility between PBAT and PPC, and enhanced the thermal stability of the composites, especially for PPC. In addition, PBAT/PPC/TGIC films at 1 phr (parts per hundreds of resin) TGIC content exhibited a tensile strength of 30.8 MPa, and an elongation at break of 860%, which are 136% and 142% of those of PBAT/PPC, respectively. Meanwhile, the water vapor transmission rate dropped by 33% at this content. The improvement of mechanics and gas barrier properties makes PBAT/PPC film better meet the requirements of food preservation packaging such as fruits and vegetables. [ABSTRACT FROM AUTHOR]

The hydrophobic modification of cellulose nanofibers (CNF) was carried out via free radical polymerization using methyl methacrylate (MMA) as the monomer to improve the compatibility between CNF and poly lactic acid (PLA). Followed by the preparation of the novel nanocomposites in combination of the organic montmorillonite and the substrate. The resulting nanocomposites were then coated on paper surface using a cast‐coating process in an attempt to improve the barrier properties towards water vapor and oxygen. In addition, the composite films are prepared via a solution casting method. The water vapor transmission rate (WVTR), water vapor permeability (WVP), oxygen transmission rate (OTR), and tensile strength of the as‐prepared films were systematically measured. The corresponding results demonstrated that the WVTR, WVP and OTR decreased with the addition of a certain content of MCNF in coatings. 0.2 wt% MCNF is the optimum content, showing the best gas resistance and tensile performance. The lowest value of WVTR and WVP are 10.30 g/(m2⋯24 h) and 3306.58 g⋯μm/(m2⋯24 h) for films with 0.2 wt% MCNF added, which is 88.23% and 26.05% lower than that of PLA composite film without NFC. [ABSTRACT FROM AUTHOR]

Cellulose nanocrystal (CNC) was prepared through the hydrolysis of concentrated sulfuric acid using commercial bagasse pulp as a raw material. The performance of the developed CNC was tested through the atomic force microscope, particle size measurement, and zeta potential analysis. The melt blending method was adopted to prepare thermoplastic polyvinyl alcohol (TPVA) and CNC‐TPVA using the glycerol (GI)‐dicondensed triethylene glycol (TEG) complex. The TPVA and CNC‐TPVA were blended with poly(butylene adipate‐coterephthalate) and polylactic acid composite material (COM) through melt extrusion granulation and blown film, and then explored the effect of CNC on the UV aging properties of materials. The complex plasticizer could effectively break the PVA hydrogen bond and reduce its melting point. It had been observed that CNC had good interface compatibility with PVA, and CNC did not affect the crystallinity of PVA, but it could weaken the hydrogen bond between GI, TEG, and PVA, thereby reduce the plasticizing effect of PVA. Compared TPVA‐COM with CNC‐TPVA‐COM, detailed information of crystallization, the thermal stability of materials and mechanical properties was presented in the UV aging process, it was found that the cross‐section of CNC‐TPVA‐COM was rough, and its unevenness formed a striped structure, and its hydrogen bond strength, diffraction peak strength and anti‐aging performance were all improved. [ABSTRACT FROM AUTHOR]

Poly(butylene adipate‐co‐terephthalate) (PBAT)/polylactic acid (PLA) composites were prepared by water‐soluble polyvinyl alcohol (PVA) and degradation‐promoting agent (DPA) which were made from acidity‐regulating KH2PO4 and halloysite by a physical layer‐by‐layer coating method. The effect of PVA and DPA on the biodegradation of PBAT/PLA composites in the cross‐sectional morphology, thermal properties, molecular structure, due to degradation was evaluated using a host of characterization methods. The results showed that PVA had a good solubilizing effect on the composite system and improved the overall compatibility. DPA had little effect on the compatibility, crystallinity, and thermal stability of the composite system, but greatly accelerated the degradation. The interior of composite material containing DPA (Com‐DPA) was shown to be severely damaged after 29 weeks of degradation, which was attributed to preferential degradation of amorphous regions of the composite by ester hydrolysis. Our results demonstrated the PVA and DPA worked synergistically to promote swelling and diffusivity of degradation products, and provided an acid environment for enhancing ester hydrolysis. This technology may have good prospects for accelerated degradation of materials in agricultural applications. [ABSTRACT FROM AUTHOR]

Irrigation and fertilization management are important for controlling agricultural soil salinity and increasing productivity in extremely arid regions. The objective of this research was to evaluate the effects of long‐term drip irrigation and organic fertilizer application on soil salinity, fruit quality and yield of jujube [Ziziphus ziziphus (L.) Karst]. We established a 7‐yr field experiment in a desert‐oasis area in Northwest China. Six treatments were performed: CK (conventional irrigation, no fertilizer), CIMF (conventional irrigation, mineral fertilizer), CIOF (conventional irrigation, organic fertilizer), DI (drip irrigation, no fertilizer), DIMF (drip irrigation, mineral fertilizer), and DIOF (drip irrigation, organic fertilizer). The results showed that soil organic carbon (SOC) concentration in soil treated with organic fertilizer increased gradually over years. Treatment DIOF favored the accumulation of SOC with the highest content and stock after 7 yr. Lower salt content in root zone was found in DIOF after 7 yr. The yield of DIOF increased annually and reached an equilibrium level after the fourth year (14.88 to 16.69 Mg ha−1). Total carbohydrate and vitamin C (Vc) of DIOF of fruit were all significantly higher than CIOF and DIMF. The boosted regression tree showed that SOC content had the highest relative contribution rate to jujube yield. Path analysis identified the most important factor affecting SOC in the drip‐fertigation system was the input of organic fertilizer, with path coefficient 0.65. Long‐term combination of drip irrigation and organic fertilizer application would be an effective strategy maintaining productivity and improve fruit quality in extremely arid areas. [ABSTRACT FROM AUTHOR]

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ABSTRACT A dopamine-functionalized poly(vinyl alcohol) (PVA) elastomer with melt processability and self-healing properties was prepared by a new chemical route of graft modification, that is, PVA carboxylation and a carbodiimide reaction. The conventional modifier for PVA sacrificed the intrinsic hydrogen-bonding interactions and dramatically decreased the mechanical strength. The modifier dopamine, as a catechol derivative, has two hydroxyl groups, which formed hydrogen bonds with the hydroxyl groups of PVA; it also has one benzene ring, which increased the thermal stability. We found that the introduction of dopamine into the PVA molecular structure lowered the melting point, improved the thermal stability, broke the crystalline structure, and enabled thermal processing. Moreover, the modified PVA possessed good mechanical properties, could be self-healed, and is believed to have potential applications in many fields. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45072. [ABSTRACT FROM AUTHOR]

Natural rubber (NR) containing graphene (GE) and graphene oxide (GO) were prepared by latex mixing. The in situ chemically reduction process in the latex was used to realize the conversion of GO to GE. A noticeable enhancement in tensile strength was achieved for both GO and GE filled NR systems, but GE has a better reinforcing effect than GO. The strain-induced crystallization was evaluated by synchrotron wide-angle X-ray diffraction. Increased crystallinity and special strain amplification effects were observed with the addition of GE. The incorporation of GE produces a faster strain-induced crystallization rate and a higher crystallinity compared to GO. The entanglement-bound tube model was used to characterize the chain network structure of composites. It was found that the contribution of entanglement to the conformational constraint increases and the network molecular parameters changes with the addition of GE and GO, while GE has a more evident effect than GO. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]