DOPO基阻燃环氧树脂便捷合成及相关性能

为永久高效提升环氧树脂阻燃性能,便捷合成了1,3-苯基-二(9,10-二氢-9-氧杂-10-磷杂菲基)二甲醇(1,3-phenyl-bis(9,10-dihydro-9-oxa-10-phosphaphenanyl)dimethanol,DOPO-1)和1,4-苯基-二(9,10-二氢-9-氧杂-10-磷杂菲基)二甲醇(1,4-phenyl-bis(9,10-dihydro-9-oxa-10-phosphaphenanyl)dimethanol,DOPO-2)2种反应型阻燃剂。它们与4,4′-二氨基二苯甲烷(4,4′-diaminodiphenylmethane,DDM)复配,再与等当量环氧树脂(E51)固化,制备了不同磷含量的DOPO基阻燃环氧体系。通过核磁共振(nuclear magnetic resonance,NMR)表征了DOPO-1和DOPO-2的结构,借助傅里叶变换红外光谱(Fourier transform infrared spectrometer,FTIR)跟踪固化历程,最后通过动态力学热分析(dynamic mechanical thermal analysis,DMTA)、热重分析(thermogravimetric analyzer,TGA)、氧指数(limiting oxygen index,LOI)测定和垂直燃烧测试(vertical combustion test,UL-94)研究了DOPO-1基和DOPO-2基阻燃环氧树脂热力学、耐热、阻燃性能与环氧体系磷质量分数、阻燃剂结构之间的关系。结果表明:1)DOPO-1/DDM和DOPO-2/DDM与E51固化后形成均相阻燃体系;2)随着磷质量分数的增加,DOPO-1基和DOPO-2基环氧树脂在700℃残炭率得到提高;3)磷的质量分数为1.0%时,环氧树脂均能达到阻燃等级UL94-V0级,磷的质量分数为1.7%就能使DOPO-1基和DOPO-2基环氧树脂LOI值分别达到40.9和41.9,且在环氧树脂阻燃性能发挥上,DOPO-2比DOPO-1更强。     

植酸三聚氰胺盐阻燃环氧树脂研究

利用生物基阻燃剂植酸三聚氰胺盐 (MPA) 阻燃改性环氧树脂并对其性能进行研究。通过红外光谱 (FTIR) 以及X射线光电子能谱 (XPS) 对MPA化学结构进行表征。利用热重分析仪 (TGA)、极限氧指数测试仪 (LOI)、垂直燃烧测试仪 (UL-94) 及锥形量热测试仪 (CC) 研究阻燃环氧树脂的热稳定性及阻燃性能。热重分析结果表明，MPA阻燃剂在800 ℃残炭达到25.6%，引入环氧树脂后可提升材料高温区热稳定性。垂直燃烧测试显示MPA在15%添加量下可赋予环氧树脂UL-94 V-0等级，表明MPA对环氧树脂有较好的阻燃效果。进一步锥形量热结果表明，MPA的加入显著降低了环氧树脂的热释放速率及总热释放，同时表现出优异的抑烟性能。     

含硅高分子阻燃材料热解阻燃机理研究进展

综述了有关含硅高分子阻燃材料的热解行为,对比不同含硅高分子聚丙烯酸甲酯(PMMA)体系材料的热释放速率、质量损失、红外光谱图,在分析热解产物中Si元素分布及形貌变化的基础上对含硅高分子阻燃材料热解阻燃机理研究进行了评述。     

聚丙烯酰胺改性硅灰基阻燃材料的制备与表征

采用硅灰、聚丙烯酰胺(PAM)、水玻璃及KOH等原料,通过溶胶-凝胶法制备有机-无机杂化阻燃材料,并将其应用于外墙外保温材料(EPS)中;利用傅里叶红外光谱(FTIR)、扫描电镜(SEM)和差式量热扫描(DSC)等测试方法对所制备的阻燃材料进行表征,研究其反应机理.结果表明:在碱性条件下,部分水解的PAM可与硅灰形成的—Si—O—链发生反应,形成结构密实的硅质层,并在燃烧过程中发展成片层结构的物质,产生隔热屏蔽效应,从而可提高材料的阻燃性能;适量PAM可使EPS的极限氧指数(LOI)达到35.5%(体积分数),阻燃级别达到UL-94V1级.     

新型阻燃环氧树脂

文章叙述的是将双环笼状磷酸酯 PEPA用于阻燃双酚 A缩水甘油醚型环氧树脂 (DGEBA) ,得到分子骨架中含有双环笼状磷酸酯结构单元的无卤膨胀型阻燃体系。实验表明 ,此膨胀阻燃体系热稳定性和膨胀成炭性能良好 ,对于环氧树脂的燃烧和火焰的蔓延能有效地抑制 ,且 PEPA对于 DGEBA具有固化、阻燃和抑烟三重作用     

建筑密封材料的阻燃改性研究

环氧树脂是建筑工程应用中常用的热塑性树脂,但其可燃性和严重的热降解性能极大地限制了在建筑领域的中应用.针对以上问题,本文提出采用聚联苯螺环二膦酰胺对环氧树脂进行阻燃改性,并通过氧指数、垂直燃烧、热失重分析、锥形量热仪、扫描电镜、热红联用等燃烧测试手段对其阻燃性能进行表征,为建筑高分子材料阻燃改性研究提供参考.     

聚丙烯酰胺改性硅灰基阻燃木材涂料

采用Na_2SiO_3和KOH混合溶液改性硅灰制备硅质溶胶,掺入聚丙烯酰胺(PAM)对其改性以提高其阻燃性能。采用锥形量热仪测试其燃烧性能,采用扫描电镜观察涂层受热前后的微观形貌。结果表明:PAM有助于改性硅灰基涂料形成更加致密的孔网结构,有助于形成连续、均匀的硅质层,当其掺量为2%时,可使样品的火灾性能指数(FPI)从71.6提高至261.8。提出了PAM在Na_2SiO_3/KOH改性硅灰涂料中的阻燃机理。     

海绵城市背景下硅砂透水砖性能研究

采用氢化双酚A型环氧树脂改性硅砂透水砖,探究硅砂粒径(35目、50目、70目)与环氧树脂掺量(2%、4%、6%、8%)对硅砂透水砖的强度、透水性能、保水性能、滤水性能以及防滑性能的影响规律。试验结果表明：当硅砂粒径为50目、环氧树脂掺量为4%时,硅砂透水砖的抗压、抗折和防滑性能最好,透水速率为1.5 mL/(min·cm²)、保水率为0.068 g/cm³,滤水率为90.2%。     

混晶TiO2制备木结构防火涂料及阻燃机理

以KOH和Na₂SiO₃改性硅灰为基料,通过溶胶-凝胶法制备水性木结构阻燃涂料。制作三聚氰胺饰面中密度纤维板试件,测量试件的氧指数,分析试样及原料的晶相变化及表观形貌,研究板钛矿/锐钛矿混晶TiO₂对其阻燃性能及微观结构的影响。结果表明,适量的TiO₂可提高其阻燃性能,当TiO₂掺量为2%时其阻燃性能最佳,可使纤维板的LOI达到31.4%,炭化体积(小室法）仅为8.2 cm³,较不添加TiO₂的样品减小了56%。混晶TiO₂在燃烧处理过程中结构稳定,有助于硅灰基水性木结构阻燃涂料在燃烧过程中发展成连续、均匀、密实的片层状结构,致使失重温度升高,热流量减小,进而提高阻燃性能。     

微胶囊化APP阻燃环氧树脂的动力学研究

通过原位聚合法利用三聚氰胺-甲醛树脂对聚磷酸铵进行了微胶囊包覆,并将其用于环氧树脂(EP)的阻燃,采用FTIR和SEM对包覆前后的聚磷酸铵样品进行表征,并用热重分析仪对阻燃环氧树脂的热失重特性进行了测试。结果表明,成功实现了对聚磷酸铵的微胶囊包覆,并且由微胶囊化聚磷酸铵组成的膨胀型阻燃剂能有效地促进环氧树脂的分解成炭。通过Kissinger法和Ozawa法研究了阻燃剂对环氧树脂热分解动力学的影响。两种方法求出的热分解表观活化能相近,EP和阻燃EP的热分解表观活化能平均值为227.808、152.309kJ/mol。     

硅烷偶联剂对环氧改性有机硅树脂耐高温性能的影响

研究了不同硅烷偶联剂对环氧改性有机硅树脂耐高温性能的影响,研究结果表明,使用KH560的环氧改性有机硅树脂耐高温性能较使用其它硅烷偶联剂的为好。通过正交实验发现,在实验选定条件下,影响环氧改性有机硅树脂耐高温性能的主要因素是偶联剂用量,其次是催化剂用量,树脂配比影响较小。     

Towards a sustainable electricity grid: Market and policy for demand-side storage and wind resources

While the net benefit of installing Distributed Energy Resources (DER) is largely locational, this work examines the system value in adding wind turbines and battery storage to a Northern Irish electricity distribution network. The DER – turbines and storage – were deployed in modules: first, for increased self-consumption of wind energy and secondly, for additional services. The results suggest that, given the current market structure, deploying the DER solely for increased self-consumption, while technically achievable, is not economically feasible. The upgrading approaches profitability and sustainability as the storage is deployed for stacked market services – and could be achieved through suitable market policies.     

不同硅源制备二氧化硅气凝胶研究进展

近年来,二氧化硅气凝胶凭借其优异性能在诸多领域被广泛应用。硅源作为制备SiO₂气凝胶最重要的组成部分,对获得结构完整、性能优良的SiO₂气凝胶至关重要。本文综述了多种硅源为前驱体的SiO₂气凝胶发展历程及制备。硅源种类划分为单一硅源和复合硅源。单一硅源主要有水玻璃、硅溶胶、工农业含硅废料及常见硅醇盐;复合硅源通过引入疏水性和功能性基团来改善结构性能,从而实现其在不同领域的应用。最后对SiO₂气凝胶硅源的选择、研究现状及前景进行探讨。     

高渗透有机硅改性环氧防腐胶的研制与应用

制备了相容性较好的低分子有机硅改性环氧树脂,配制了两种不同温度环境下的双组分高渗透型有机硅改性环氧防腐胶,讨论了浆料中双组分配比、环境温度、催干剂、有机硅改性环氧树脂和有机硅含量等对浆料的固化、渗透性、强度和憎水性能及防腐性能的影响,提出了浆料的几个主要应用实践与方向.     

An analysis of the DER adoption climate in Japan using optimization results for prototype buildings with U.S. comparisons

This research demonstrates economically optimal distributed energy resource (DER) system choice using the DER choice and operations optimization program, the Distributed Energy Resources Customer Adoption Model (DER-CAM). DER-CAM finds the optimal combination of installed equipment given prevailing utility tariffs and fuel prices, site electrical and thermal loads (including absorption cooling), and a menu of available equipment. It provides a global optimization, albeit idealized, that shows how site useful energy loads can be served at minimum cost. Five prototype Japanese commercial buildings are examined and DER-CAM is applied to select the economically optimal DER system for each. Based on the optimization results, energy and emission reductions are evaluated. Significant decreases in fuel consumption, carbon emissions, and energy costs were seen in the DER-CAM results. Savings were most noticeable in the prototype sports facility, followed by the hospital, hotel, and office building. Results show that DER with combined heat and power equipment is a promising efficiency and carbon mitigation strategy, but that precise system design is necessary. Furthermore, a Japan–U.S. comparison study of policy, technology, and utility tariffs relevant to DER installation is presented.     

酸酐用量对固化环氧树脂热性能的影响

研究了酸酐/环氧当量比r对双酚A型E-44环氧树脂固化物耐热性能的影响。结果表明:随着酸酐/环氧当量比的增加,固化产物的热变形温度HDT,玻璃化转变温度Tg以及热分解温度也不断的提高,在酸酐与环氧树脂的当量比为1.1∶1时,固化产物有最佳的耐热性能。     

Physical and mechanical properties of chemically grouted sand

It is generally accepted that only chemical grouts or solutions are available to penetrate and fill narrow joints or soils with very small pore size. Over the last 30 years a few hundreds of different compounds have been used for this purpose showing a wide spectrum of properties. Epoxy resins are among the compounds that are commonly used in building restoration because of their high strength and durability against mechanical or physical erosion. The purpose of this paper is to investigate the improvement of the physical properties (water permeability, porosity and dry unit weight) and mechanical properties (compressive strength, elastic modulus, splitting tensile strength and strength under triaxial stress conditions) of fine sand mixed with a water-soluble two component epoxy resin is, since there is not any published data about the efficiency of such high strength material in ground improvement. The experiments were carried out using different solutions of epoxy resin, which had epoxy resin/water (ER/W) ratio of 2.0, 1.5, 1.0 and 0.5. Cylindrical specimens were prepared by mixing fine sand with an adequate quantity of epoxy resin and were used for compression, splitting tensile and triaxial strength tests. Development of compressive and splitting tensile strength was evaluated from tests at the ages of 3, 7 and 28 days whereas strength under triaxial conditions was determined on specimens cured for 28 days.The results of this study indicate that the epoxy resin solutions, especially the solutions with low water content resulted in higher strength, lower porosity and lower water permeability of the sand, improving significantly the physical and mechanical properties of the fine sand.     

CFRP strengthened butt-welded very high strength (VHS) circular steel tubes

This paper investigates the behavior of carbon fibre reinforced plastics (CFRP) strengthened butt-welded very high strength (VHS) circular steel tubes. The VHS steel has a yield stress of 1350 MPa and an ultimate strength of 1500 MPa. Three types of epoxy resins with different lap shear strength were used. Tests were conducted to determine the lap shear strength between CFRP and VHS steel tubes. A total of 21 butt-welded VHS tubes strengthened with CFRP were tested in axial tension. Three kinds of failure modes, i.e. adhesive failure, fiber tear and mixed failure were observed. The suitable epoxy adhesive for strengthening VHS tubes was recommended. A significant strength increase was achieved using CFRP–epoxy strengthening technique. A theoretical model was developed to estimate the load carrying capacity of butt-welded VHS tubes strengthened using CFRP.     

甲醛改性松香环氧树脂／纳米SiO2复合材料的制备与表征

用硅烷偶联剂将SiO2表面处理后再与甲醛改性松香环氧树脂混合,将不同含量的SiO2均匀地分散到环氧树脂固化体系中,然后用HHPA固化可制备出纳米复合材料。初步研究了无机纳米粒子SiO2对FMRE复合材料热性能和力学性能的影响。适量的SiO2对FMRE／HHPA固化物有明显的增韧增强作用,拉伸强度和断裂伸长率均有不同程度的提高;纳米复合材料的玻璃化转变温度可在小范围内提高,不同的添加量可提高玻璃化转变温度2-8℃。在相同的时间内,FMRE／HHPA／SiO2纳米复合材料的疏水性大于FMRE/HHPA固化物的疏水性。     

Flexural behavior of polymer concrete

The flexural behavior of polymer concrete (PC) made with different types of resins was evaluated in this study. A total of 54 beams was tested under four-point loading (36 singly reinforced and 18 unreinforced) to examine different parameters that influence the behavior of polymer concrete in flexure. The beams were made of resins that are widely used in concrete repair works in the Gulf region. Three types of polymer resins were investigated: two types of epoxy from two different manufactures and one type of polyester. The studied parameters included the percentage of polymer in the concrete mix (three percentages were used: 9, 12 and 15%), and the reinforcement ratio (ρ=0, 0.0042 and 0.0116). The results show that the modulus of rupture and ultimate compressive strains for PC are much higher than that of ordinary Portland cement concrete. The beams showed a very ductile behavior and high ductility factors were obtained. The test results were compared with the equations used in the ACI design method and several recommendations are made to modify some of those equations to become more suitable for the flexure design of PC.