最新刊期
卷 26 ， 期 3 ， 2013
- 摘要：To pursue high power conversion efficiency (PCE) of polymer solar cells(PSCs), more and more new active layer materials, especially donor materials have been developed in the past several years. Among them D-A type low band-gap conjugated polymers based on benzo-[1,2-b:4,5-b’]dithiophene boost the PCE of polymer solar cells greatly, its efficiency is as high as 10.6%. This paper reviews the progress of D-A type narrow band-gap conjugated polymers based on benzo[1,2-b:4,5-b’]dithiophene and their applications in polymer solar cells. Emphasis is placed on the relationships among material structures and properties of PSCs. The methods for improving the PCE of PSCs based on benzo[1,2-b:4,5-b’]dithiophene conjugated polymers are summarized by improving the open circuit voltage, short circuit current and fill factor.关键词：Polymer solar cells;Benzo[1,2-b:4,5-b’]dithiophene;Low band-gap;Open-circuit voltage;Short-circuit current;Fill factor
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发布时间：2022-09-18 - 摘要：As a new kind of green solvents, ionic liquids are greatly used in processing of natural polymer material. Chitosan, obtained by N-deacetylation of Chitin, which is the most abundant natural alkaline polysaccharides. Chitosan is a biocompatible polymer that is reported to exhibit a great variety of useful properties such as bio-degradability, hygroscopic, antibacterial, spinnablity and film forming, and has a promising future used in medicine, foods, textile, paper making and daily chemical industry. In recent years, ionic liquids have been studied in chitosan as green solvents, reaction media for homogeneous chitosan derivatizations, composites processing and electrochemical biosensors. In this paper, recent developments are reviewed with 54 refs.关键词：Ionic liquids;Chitosan;Dissolution;Homogeneous reaction;Biosensors
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发布时间：2022-09-18 - 摘要：Polymer/surfactant systems can be roughly classified into three categories such as neutral/ionic, charged/ionic, and unspecified/nonionic ones, in terms of the respective surface charge of the two partners. On this ground, the interactions between the polymer and surfactant in aqueous phase are reviewed in this article. It is found that, in most cases, polymers can interact with surfactants in aqueous media by forming complexes. The driving forces binding polymers and surfactants into complexes are mainly due to the hydrophobic bonding, electrostatic attraction as well as hydrogen bonding, individually or collaboratively, depending on the physicochemical properties of the reactants, such as charge attributes and lengths of the hydrophobic chains. In addition, the formation mechanism and structure of the resultant complexes are also influenced more or less by pH, temperature, and ionic strength.关键词：Polymer/surfactant system(s);Aqueous phase;Interaction;Complexes;Driving force(s)
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发布时间：2022-09-18 - 摘要：Cyclodextrin polymers are polymeric derivatives which have multiple cyclodextrins, and they have the high performance of both β-cyclodextrin and polymers, so they are widely used in the areas including molecular recognition, separation and analytical techniques, biomedical engineering, environmental protection, etc. The synthesis of cyclodextrin polymers has been given abroad attention, and the functionalization of β-cyclodextrin monomer is the key step of synthesis of β-cyclodextrin polymers. The synthesis methods of β-cyclodextrin monomer with functional groups were reviewed, including modifying it to β-cyclodextrin monomer with highly active functional groups, to cyclodextrin monomers carrying vinyl group and to cyclodextrin monomers with multiple substituted functional groups, etc.关键词：β-Cyclodextrin;Functionalization;Synthesis
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发布时间：2022-09-18 - 摘要：The risk of antibiotics on environment ecology and human health can never be neglected. Molecularly imprinted technology as a kind of efficient separation method is used to extract antibiotic residue from environment water sample. Based on comprehensive literatures, the synthetic methods of molecularly imprinted polymer (MIP) and related factors are outlined. The recognition ability of several kinds of common antibiotics MIP and application of MIP on environmental antibiotic residues are summarized.关键词：Molecularly imprinted polymer;Antibiotic;Environment sample
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发布时间：2022-09-18 - 摘要：In recent years, many researchers have an increasing interest in selenophene based polymers and oligomers in organic optoelectronic devices. So far, organic solar cells based on polyselenopheno[3,4-b]selenophene-co-benzodiselenophene(PSeB2) show higher power conversion efficiency of 6.87%, eld-effect transistors based on PSeDPP(P28), consisting of selenophene and 3,6-dithiophen-2-yl-2,5-dialkylpyrrolo[3,4-c]pyrrole-1,4-dione (DPP), show higher hole mobility of 1.62cm2/(Vs). PLED device based on PFO-DDSTQ show near infrared emission at 860nm. This paper summarizes the progress of selenophene polymers and oligomers based organic optoelectronic devices.关键词：Selenophene;Organic solar cells (OSCs);Feld-effect transistors(FETs);Light emitting diode (LED)
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发布时间：2022-09-18 - 摘要：We studied the ternary blend films composed of low-degree of polymerization poly[2,6-(4,4-bis-(2-ethylhexyl)-4H-cyclopenta[2,1-b;3,4-b’]dithiophene)-alt-4,7-(2,1,3-benzothiadiazole)] (LDP-PCPDTBT), [6,6]-phenyl-C61-butyric acid methyl ester (PC61BM), and polymethylmethacrylate (PMMA), processed with and without 1,8-dibromooctane as solvent additive. The LDP-PCPDTBT and PC61BM phases in the PMMA matrix were characterized amorphous and crystalline, respectively, without the additive processing, while both the crystallinity of the LDP-PCPDTBT component and the aggregation of PC61BM component could be significantly promoted with the additive processing. The power conversion efficiency of solar cell was increased 50% by the additive processing, as a result of the increased open-circuit voltage and the optimized phase separation of LDP-PCPDTBT and PC61BM in the PMMA matrix. The current research indicates that the low-degree of polymerization alternating copolymers can be recycled as efficient electron donors in association with PMMA, helpful for reducing the material cost of organic solar cells.关键词：Polymer solar cells;Low-degree of polymerization alternating copolymer;PMMA;1,8-Dibromooctane
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发布时间：2022-09-18 - 摘要：Ring-opening polymerization of polyglycolic acid (PGA) with high molecular weight under high pressure in reaction still was studied in the presence of glycolide(GA) as monomer and tin(II) chloride dihydrate as catalyst. The influence of synthesis condition on weight-average molecular weight (Mw) was investigated by a series of single factor experiments. Orthogonal experiment was carried out to obtain optimum process according the result of single factor experiments. Critical values of technological conditions were obtained by the Analysis of the result of orthogonal experiment with STATISTICA6.0. The weight-average molecular weight of Polyglycolic acid was as up to 1.61×105 under optimum conditions as follow:reaction temperature 196.5℃, reaction time 3h, catalyst concentration n(cat.)/n(GA)=1.7×10-5.关键词：High pressure;Polyglycolic acid;Glycolide;Ring-opening polymerization;Orthogonal experiment
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发布时间：2022-09-18 - 摘要：In order to research low rank coal conversion mechanism, coal macromolecule is needed to be explored deeply. In this paper, Elemental composition and infrared spectroscopy of Fushun long flame coal were firstly tested. After dividing peaks of infrared spectroscopy, farH, H/C, side strain length and fa were calculated subsequently, software ChemOffice Ultra 2010 was used to draw Coal Macromolecule Structural Model. Connecting formats of different atoms were regulated in order to make sure these parameters are close to test values. In this way, Fushun long flame coal structural model was obtained, with molecular formula as C194H193CaN3O27.关键词：Infrared spectroscopy;Long flame coal;Coal macromolecule;Structural model;Aromatic carbon ratio
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发布时间：2022-09-18 - 摘要：Poly(L-lactic acid) with low viscosity average molecular weight prepared by melt polycondensation of L-lactic acid was extended by triphenyl phosphate and 1,4-butanediol diglycidyl ether, respectively. Triphenyl phosphate and 1,4-butanediol diglycidyl ether were effectively chain extender, which was confirmed by the results that viscosity average molecular weight was promoted obviously after chain extension of PLLA. However, viscosity average molecular weight of PLLA-TPPi and PLLA-BDDE did not change with the content of TPPi or the content of BDDE, but exhibited a peak value. Tg of PLLA-TPPi and PLLA-BDDE increased with the increasing of viscosity average molecular weight. Compared with PLLA-BDDE, the structure of TPPi in PLLA-TPPi chain was more effective to promote the crystallization of PLLA.关键词：Melt polycondensation;Chain extension;Triphenyl phosphate;1,4-Butanediol diglycidyl ether
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发布时间：2022-09-18 - 摘要：Acetylated straw-graft-poly (ε-Caprolactone) copolymer (ACSW-g-PCL) is synthesized with the grafting copolymerization of acetylated straw (ACSW) and ε-Caprolactone, in which the acetylated straw is synthesized with the acylation of the ground rice straw powder. The influences of time, temperature and amount of ε-Caprolactone on the grafting percentage (G%) are studied. The maximum grafting percentage (39%) was obtained at thereaction temperature 140℃, reaction time 10h and the weight ratio of caprolactone to acetylated straw 2:1. Thecomposition and structure of ACSW-g-PCL were analyzed by various methods including FTIR spectroscopy,1H NMR, SEM analysis, XRD and thermal performance testing. The results show that the PCL has been grafted onto the ACSW, and the DSC proved that the thermo stability and thermoplastic property of ACSW-g-PCL are much better than that of the original straw.关键词：Rice straw;Acetylation;ε-Caprolactone;Graft copolymerization;Thermoplastic
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发布时间：2022-09-18 - 摘要：In this paper, fly ash modified by three different coupling included Si-69, titanate and stearic acid was used as filler to reinforce silicone rubber. The structure and morphology of modified and unmodified fly ash were characterized using by Fourier transform infrared spectroscopy and scanning electron microscope. The mechanical and flame retardancy properties of composites were compared. The result showed that the structure of modified fly ash was changed and the surface area was improved observed by FTIR and SEM. The mechanical properties and flame retardancy performance of modified fly ash/silicon rubber composites were greatly improved compared with unmodified fly ash. The best property of silicone rubber composite was added 1wt% fly ash modified by stearic acid.关键词：Fly ash;Silicone Rubber;Modified;Flame retardancy
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发布时间：2022-09-18 - 摘要：A superhydrophobic surface was fabricated by grafting the copolymers onto multiwalled carbon nanotubes (MWCNT) using free radical polymerization. The results showed that α-methylstyrene and butylmethacrylate can prepare copolymers PAB, and the thermal degradation products can graft onto MWCNT to obtain superhydrophobic surface with maximum static water contact angle of 165° and sliding angle of less than 3°. The result of SEM indicated that grafting copolymers increased the gap between tubes and roughness of surfaces, and provided conditions for decreasing surface energy. Droplet test of different pH value and the effect of exploring time showed that the prepared surfaces have excellent stability and durability.关键词：Superhydrophobic;Carbon nanotubes;Free radical polymerization;Grafted;Stability
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发布时间：2022-09-18 - 摘要：The macromolecules chain transfer agent was synthesized by using styrene (St) as monomer and 2-cyanoprop-2-yl1-dithionaphthalate (CPDN) as RAFT agent. The different block ratio of copolymers P(St-b-A171) were synthesized by dvinyltrimethoxysilane (A171) and macromolecules chain transfer agent. The structure of block copolymer was characterized by 1H NMR, gel permeation chromatography GPC, dynamic mechanical analysis (DMA) and other methods. The results showed that the number-average molecular weight of block polymer was increased from 10400 to 14000 and PDI index increased from 1.42 to 1.58 as the block ratio of nSt/nA171 increased from 1:0.15 to 1:0.45. The contact angle of block polymer film was increased from 78.4° to 89.6°. Through the analysis above, the nSt/nA171 block ratio have great influence on the performance of P (St-b-A171).关键词：Styrene;Chain transfer agent;Vinyltrimethoxysilane;Block copolymers
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发布时间：2022-09-18 - 摘要：Polystyrene (PS) particles with a narrow molecular weight distribution were synthesized by dispersion polymerization in alcohol, using polyvinylpyrrolidone (PVP) as dispersant and azobisisobutyronitrile (AIBN) as initiator. Influences of reaction tempreture, reaction time, initiator concentration and monomer concentration on conversion of styrene and molecular weight distribution of PS were researched. Furthermore the morphology, molecular structure, and properties of the PS particles were characterized by scanning electron microscope (SEM), gel permeation chromatography (GPC), fourier transform infrared spectrum (FT-IR), and thermogravimetry (TG). Results show that the monomer conversion of styrene is up to 87.8%, when the monomer concentration of styrene is 20%, the dosage of initiator is 0.7%, reaction temperature is 75℃, and reaction time is 13h. Under this condition, the spherical PS particles prepared have a good sphericity, a high molecular weight (1.66×105), and a narrow molecular weight distribution (1.21).关键词：Dispersion polymerization;Narrow molecular weight distribution;Polystyrene;Synthesis
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发布时间：2022-09-18 - 摘要：Energetic tetrazole-metal complexes is of great significance and good prospects in national defense area. Some preliminary researches on energetic tetrazole-metal complexes for initiating agent were conducted internationally. The complexes with tetrazole-derivatives, especially with 5R-tetrazole negative ions, as ligands, will be well developed for initiating agent. To probe the future use potentialities as initiating agent and to improve their properties and safety, the recent research situation of the advanced tetrazole-metal complexes is necessary to be reviewed.关键词：Green initiating agent;Tetrazole;Energetic-metal complexes
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发布时间：2022-09-18
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