POLYMERS FOR ADVANCED TECHNOLOGIES
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2019
·Vol. 30
·期 7
·1684-1695
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IF 2.162
Jingshang Zhou,Miaojun Xu,Xiaohan Zhang,Yang Leng,Yintong He,Bin Li
The unsaturated polyester resins (UPR) were usually applied in electronic equipment, but the intrinsic flammability severely retrained their application. A mono-component flame retardant poly (piperazine methylphosphonic acid neopentylglycol ester) (PPMPNG) made in our lab was selected and applied to improve their flame retardant performance. The UPR thermosets achieved UL-94 V-0 grade during vertical burning tests and the limiting oxygen index was as high as 32.1% when 15 wt% PPMPNG was incorporated. PPMPNG promoted the decomposition and carbonization of UPR materials in advance during heating process, and the residual mass was effectively enhanced at high temperature. The flame retardant mechanism of UPR/PPMPNG thermosets was investigated by pyrolysis-gas chromatography/mass spectrometry tests, and the measurement of the morphologies and chemical components of the char residue. The phosphine oxygen radical was generated and then quenched the active free radicals in gas phase. Moreover, the av-EHC of FR-UPR was declined from 15.8 MJ kg −1 of pure UPR to 8 9 MJ kg −1 corresponding a reduction of 43.6%, which also verified the flame retardant effect in gas phase. The compact, integrated, and graphitized char layer was produced on materials surface and then exerted excellent barrier effect in condensed phase. Thus, the UPR/PPMPNG composites were conferred superior flame retardant properties.
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高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2019
·Vol. 30
·期 4
·879-888
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IF 2.162
Rui Gao,Shuguang Wang,Keqing Zhou,Xiaodong Qian
In the present work, a facile and environmental method was developed to fabricate the novel functionalized MoS 2 hybrid. Firstly, MoS 2 nanosheets were coated with polydopamine (PDA) through the self-polymerization of dopamine (MoS 2 -PDA) in a buffer solution. Then the decoration of Ni(OH) 2 on the MoS 2 -PDA was synthesized because of the strong affinity of Ni 2+ with hydroxyl groups in PDA. Finally, the as-synthesized MoS 2 -PDA@Ni(OH) 2 was introduced into poly(lactic acid) (PLA) matrix to explore flame retardancy, thermal stability, and crystalline property of the composites. As confirmed by X-ray diffraction (XRD), Fourier-transform infrared spectrometer (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA), the MoS 2 nanosheets were dually modified with PDA and Ni(OH) 2 without destroying the original structures. The thermal degradation of PLA with MoS 2 -PDA@Ni(OH) 2 generated a notably higher yield of char. Moreover, the crystallization rate of composites is higher than neat PLA. The cone calorimeter test revealed that the introduction of 3% MoS 2 -PDA@Ni(OH) 2 resulted in lower Peak Heat Release Rate (PHRR) (decreased by 21.7%). Thus, the research provided an innovative functionalization method for manufacturing PLA composites with high performances.
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高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2019
·Vol. 30
·期 4
·963-972
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IF 2.162
Sheng Xiang,Lidong Feng,Xinchao Bian,Bao Zhang,Bin Sun,Yanlong Liu,Gao Li,Xuesi Chen
To obtain an effective compatibilizer for the blends of poly(L-lactide) (PLLA) and poly(ε-caprolactone) (PCL), the diblock copolymers PCL- b -PLLA with different ratios of PCL/PLLA (CL/LA) and different molecular weights ( M n ) were synthesized by ring-opening polymerization (ROP) of L-lactide with monohydric poly(ε-caprolactone) (PCL-OH) as a macro-initiator. These copolymers were melt blended with PLLA/PCL (80/20) blend at contents between 3.0 and 20 phr (parts per hundred resin), and the effects of added PCL- b -PLLA on the mechanical, morphological, rheological, and thermodynamic properties of the PLLA/PCL/PCL- b -PLLA blends were investigated. The compatibility between PLLA matrix and PCL phase was enhanced with decreasing in CL/LA ratios or increasing in M n for the added PCL- b -PLLA. Moreover, the crystallinity of PLLA matrix increased because of the added compatibilizers. The PCL- b -PLLA with the ratio of CL/LA (50/50) and M n ≥ 39.0 kg/mol were effective compatibilizers for PLLA/PCL blends. When the content of PCL- b -PLLA is greater than or equal to 5 phr, the elongations at break of the PLLA/PCL/PCL- b -PLLA blends all reached approximately 180%, about 25 times more than the pristine PLLA/PCL(80/20) blend.
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高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2019
·Vol. 30
·期 5
·1226-1233
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IF 2.162
Mingshuai Fan,Yongjie Zhang,Xiaopei Li,Beidi Zeng,Shangtao Chen,Wenqin Zhu,Shuwei Wang,Jing Xu,Na Feng
It is of great significance to synthesize polyolefin/polysiloxane hybrid materials due to their unique combination of crystalline polyolefin segments and semiorganic polysiloxane segments. Herein, we report the syntheses of a novel polypropylene/polydimethylsiloxane (PP -g- PDMS) graft copolymer via the coupling reactions between maleic anhydride-grafted PP and monoaminopropyl-terminated PDMS. The chemical structures of PP -g- PDMS have been characterized by Fourier transform infrared (FTIR), nuclear magnetic resonance (NMR), and gel permeation chromatography (GPC). The correlation between reaction conditions and the structural parameters of PP -g- PDMS has been established. Consequently, the potential applications of resultant PP -g- PDMS were investigated, and the results showed that PP -g- PDMS can serve as an efficient compatibilizer in heterogeneous PP/PDMS blend system and also as an ideal processing aid for high-viscosity PP.
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高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2019
·Vol. 30
·期 11
·2918-2926
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IF 2.162
Nan Wang,Shiyan Guo,Jun Liao,Qing Zhu,Chengyao Hu,Jichuan Huo
We established a novel, easy, and versatile method of obtaining diverse and controllable interphases between epoxy resin and fillers. The method involved the co-deposition of polydopamine (PDA) and polyethyleneimine (PEI) with different molecular lengths on boron nitride (BN) surface. The obtained PDA/PEI-modified BN composites showed significantly improved mechanical properties, including tensile strength, toughness, and elongation at break. For example, the tensile strength, fracture toughness, and elongation at break of EP composite increased by 51%, 132%, and 170% compared with EP when the PEI molecular weight was 10 000, respectively. These results suggested that the interphases between BN and EP matrix can be adjusted by changing the molecular lengths of grafted modifiers, thereby offering a new method for the reasonable designing and exploitation of the BN-based composite materials.
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高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2019
·Vol. 30
·期 7
·1543-1554
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IF 2.162
Haichao Liu,Sheng Li,Zhiyong Zhang,Bin Li,Miaojun Xu
A novel mono-component flame-retardant additive poly (dimethylol melamine piperazine pyrophosphate) defined as PDMPP was synthesized from formaldehyde, melamine, and piperazine pyrophosphate. Its chemical structure was well characterized by Fourier transform infrared spectroscopy, 13 C and 31 P solid-state nuclear magnetic resonance, and elemental analysis tests. PDMPP was incorporated into polypropylene (PP) matrix, and the fire-retardant performance, thermal properties, and water resistance of PP composites were investigated in detail. PP/23 wt% PDMPP composites before and after water resistance tests both achieved UL-94V-0 grade during vertical burning tests, and the limiting oxygen index was slightly declined from 26.7% to 26.3%. Small amount of PDMPP was extracted by hot water, and the weight loss percentage was 0.67% during water resistance tests. The piperazine and triazine rings in PDMPP contributed to a much better char-forming capability, and then a greatly expanded and coherent char residue was generated during combustion and exhibited excellent isolation effect. The heat release rate, carbon monoxide production, and smoke production rate of the flame-retarded PP composites before and after water resistance tests were effectively suppressed to a low level. Consequently, the introduction of PDMPP apparently improved the fire safety of PP composites as well as excellent water-resistant performance.
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高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2019
·Vol. 30
·期 11
·2846-2859
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IF 2.162
Li Yang,Weijun Zhen
Phosphorylated graphene oxide (PGO) was prepared by using phosphoric acid as functional reagent, and PGO was grafted with poly(L-lactide) (PGO-PLLA) by ring-opening polymerization of L-lactide as monomer under nano-ZnO catalyst. The results of the orthogonal analysis showed the optimum reaction conditions to be as follows: the reaction temperature of 170°C, reaction time of 14 hours, the mass ratio of PGO of 10 wt%, and the mass of nano-ZnO of 1 wt%. PGO-PLLA was characterized by fourier transform infrared spectroscopy, gel permeation chromatography, and X-ray photoelectron spectroscopy, which demonstrated that the PLLA molecular chains were successfully grafted onto the surface of PGO. Poly (lactic acid)/PGO-PLLA nanocomposites (PLA/PGO-PLLA) were prepared by melt intercalation. Mechanical test and fracture scanning electron microscopy showed that PGO-PLLA (0.3 wt%) improved impact strength of PLA by 52.19%, which resulted in ductile fractures surface of PLA/PGO-PLLA. Microcalorimetry and thermal degradation kinetics proved that PGO-PLLA improved the thermal stability of PLA. Polarized optical microscopy and differential scanning calorimetry confirmed that PGO-PLLA increased crystallization rate and spherulite kernel density of PLA, and crystallinity of PLA/PGO-PLLA reached to 22.05%. Rheological behavior proved that PGO-PLLA increased the self-lubricity of PLA. Enzymatic degradation results illustrated that PGO-PLLA had some inhibition for the biodegradability of PLA based nanocomposites.
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高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2019
·Vol. 30
·期 6
·1386-1393
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IF 2.162
Chongyi Zhu,Dan Chang,Xiao Wang,Danxia Chai,Lili Chen,Alideertu Dong,Ge Gao
As a significant role in subcategory of halogen antibacterial field, amphiphilic N -halamine polymers show a promise as potential antimicrobials having a broad spectrum of microorganisms, long-term stability, and renewal of their antibacterial properties. By controlling the process parameters, electrospinning has been well recognized as a versatile and effective method being capable of making fibers and could be easily engineered with desired pore size and porosity to enhance the antimicrobial properties. The amphiphilic N -halamine P (ADMH-MMA-HEMA) terpolymer fibers showed efficient antimicrobial properties against both Gram-positive and Gram-negative bacteria within brief contact time. The result meant that the polymer fibers of macromolecular architecture with control of structural parameters such as hydrophobicity/hydrophilicity balance achievement improved antimicrobial activities via electrospinning technique. In vitro cytotoxicity study demonstrated that the polymer was biocompatible. As a result, the integration of amphiphilic antibacterial materials and the electrospinning technique provided us a feasible method to fabricate biocompatible antimicrobial products easily with low manufacturing cost and would be applied in many promising application areas.
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高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2019
·Vol. 30
·期 12
·2968-2976
·
IF 2.162
Yan Wang,Jinhui Liu,Lin Xia,Mei Shen,Zhenxiang Xin,Jinkuk Kim
Eucommia ulmoides gum (EUG) is a renewable and sustainable polymer, which could be used as rubber or plastic by altering its crosslinking density while the complicated extracting process and nonpolar molecular chains limited its application. In this effort, a novel extraction method was introduced, which could simplify the extraction process of EUG. Then, the extracted EUG-chloroform (CHCl 3 ) solution was directly used to prepare epoxidized EUG (EEUG) with an epoxy degree of 40.0% to improve its polarity. The epoxidized natural EUG exhibiting both polar and nonpolar motives had an advantage in working as an interfacial compatibilizer for polymer composites, especially bio-based composites due to its inherent biocompatibility. Accordingly, the role of EEUG in modifying the interface of styrene-butadiene rubber (SBR)/silica composites were explored. The results showed that EEUG in SBR/silica composites acted not only as a compatibilizer but also as a constructure generating better mechanical properties than other compatibilizers, such as silane couplings, Si-69 and KH-550, and epoxidized natural rubber (ENR). The simplified extracting process and the epoxy modification of EUG would extend its application in rubber materials, medical materials, and biopolymer materials.
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高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2019
·Vol. 30
·期 9
·2353-2360
·
IF 2.162
Mengjie Huang,Shaoyu Lü,Yanzheng Ji,Zengqiang Wang,Shao-Fei Zhang,Taomei Qi,Jia Yan,Tao Li,Yongming Liu,Mingzhu Liu
Thrombosis has become one of the major diseases harmful to human health. The new-generation thrombolytic drug nattokinase (NK) has been used in the treatment of thrombosis because of its high safety, small side effects, and good thrombolytic effect. However, its application is limited because of its short half-life and inactivation in external environments. Therefore, it is necessary to retain the enzyme activity of NK to improve its environmental stability. In this study, NK was decorated by bonding peptide dendrimers to improve its enzymatic activity. Polyglutamic acid dendrimers of generation 2 were firstly synthesized, and then the targeting molecule arginine-glycine-aspartic acid (RGD) was linked to dendrimers by reaction of carboxyl and amino groups. Subsequently, polyglutamic dendrimer particles were bonded on the periphery of NK by chemical reaction and were used as carriers for NK. The carriers were characterized by Fourier transform infrared (FTIR) and thermogravimetric (TG) analysis, and their size and morphology were evaluated. Their enzyme activity at different pH and temperature was determined, and improved NK activity was achieved after bonding with dendrimers under acid and alkaline conditions and high temperature. Their thrombolytic properties were evaluated by in vitro and in vivo thrombolytic experiments. Effective thrombolytic effect was observed. This study indicated that the NK carrier prepared by chemical bonding may have applications in the treatment of thrombosis.
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高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2019
·Vol. 31
·期 1
·146-159
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IF 2.162
Shanshan Li,Mingfeng Chen,Liping Su,Xiuhuang Lin,Canpei Liu
Multifunctional epoxy resins with excellent, thermal, flame-retardant, and mechanical properties are extremely important for various applications. To solve this challenging problem, a novel highly efficient multielement flame retardant (PMSBA) is synthesized and the flame-retardant and mechanical properties of modified epoxy resins are greatly enhanced without significantly altering their and thermal properties by applying the as-synthesized PMSBA. The limiting oxygen index value reaches up to 29.6% and could pass the V-0 rating in the UL-94 test with even low P content (0.13%). Furthermore, cone calorimetry results demonstrate that 30.3% reduction in the peak heat release rate for the sample with 10.0 wt% PMSBA is achieved. X-ray photoelectron spectroscopy and scanning electron microscopy indicate that Si-C, Si-N, and phosphoric acid derivative can be transformed into a multihole and intumescent char layer as an effective barrier, preserving the epoxy resin structure from fire. More importantly, mechanical properties such as impact strength, tensile strength, and flexural strength are also increased by 63.86%, 33.54%, and 15.65%, respectively, which show the incorporation of PMSBA do not deteriorate the mechanical properties of modified epoxy resins. All the results show that PMSBA is a promising strategy for epoxy resin with satisfactory, thermal, flame-retardant, and mechanical properties.
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高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2019
·Vol. 31
·期 1
·135-145
·
IF 2.162
Danqi Yang,Luming Dong,Xudong Hou,Weikang Zheng,Jian Xiao,Jianzhong Xu,Haiyun Ma
A highly cross-linked poly (cyclotriphosphazene-resveratrol) microsphere (PRV) was synthesized by using hexachlorocyclotriphosphazene (HCCP) and bio-based resveratrol (REV) as raw materials, and the obtained PRV microspheres were applied to improve the flame retardancy and mechanical property of epoxy resin (EP). The TGA results showed that the PRV microsphere is an excellent charring agent and the char yield is as high as 62% at 800°C. The incorporation of PRV makes the initial degradation earlier yet significantly increases the char residue of EP composites. Moreover, the introduction of PRV microspheres into EP greatly promoted the flame retardancy performance. Under 3% of addition of PRV microspheres, the peak heat release rate (PHRR) and total heat release (THR) were decreased by 58.3% and 29.6%, respectively, the limited oxygen index (LOI) value was increased to 29.7% from 25.3% of pure EP. In addition, because of the uniform distribution in EP matrix and the enhancing effect of PRV microspheres, the mechanical properties including tensile modulus of EP composites were strengthened. PRV microspheres in this paper provide a possibility to synthesize a dual functional filler, which acts as both flame retardant and strengthening agent.
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高影响因子
危险品化学品经营许可证（带存储）