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1.
为了提高环氧树脂(EP)的阻燃性能,将双基阻燃剂六(4-(9,10-二氢-9-氧杂-10-磷杂菲-10-硫化物)-羟甲基苯氧基)环三磷腈(HAP-DOPS)和六苯氧基环三磷腈(HPCTP)/9,10-二氢-9-氧杂-10-磷杂菲-10-硫化物(DOPS)分别添加到EP中,在含磷量为1.8%(质量分数)时,对比研究了磷腈、磷杂菲基团在分子内和分子间双基协同阻燃对EP性能的影响,探索了其阻燃规律,同时研究了不同添加量的HAP-DOPS对EP的热稳定性、阻燃性能和成炭性能的影响,并分析了其阻燃机理。结果表明,15%HAP-DOPS/EP的极限氧指数(LOI)值提高至31.4%,垂直燃烧测试(UL-94)达到V-0级;当HPCTP/DOPS/EP的含磷量为1.8%,PHPCTP∶PDOPS=1∶1时,复合体系的LOI值为31.2%,达到UL-94 V-0级,即阻燃剂HAP-DOPS和HPCTP/DOPS均能有效改善EP的阻燃性能,但HAP-DOPS在降低热释放方面更有优势,HAP-DOPS/EP的潜在火灾危险性低于HPCTP/DOPS/EP。残炭分析...  相似文献   

2.
单一的磷杂菲、磷腈类阻燃剂的阻燃效果有限,为了改善9,10-二氢-9-氧杂-10-磷杂菲-10-硫化物(DOPS)对环氧树脂(EP)的阻燃效果,将DOPS和六苯氧基环三磷腈(HPCTP)复配应用于EP。在总含P量为1.2wt%时,通过调整磷杂菲和磷腈阻燃剂中含P量的比例,将DOPS和HPCTP复配添加到EP中,制备EP复合材料。利用极限氧指数(LOI)、垂直燃烧(UL-94)、热重(TG)、锥形量热(CONE)、扫描电镜-能量色散X射线谱(SEM-EDS)、热重-红外光谱联用(TG-IR)等测试手段研究不同比例的磷杂菲和磷腈基团对EP热稳定性和阻燃性能的影响,探究双基协同阻燃规律和机制。研究结果表明:P、S元素之间存在协同阻燃作用,当总含P量为1.2wt%时,复合体系中随着含S量的增加,HPCTP-DOPS/EP的LOI值和UL-94等级逐渐升高,当HPCTP和DOPS中的含P量比为0.2∶1时,HPCTP-DOPS/EP的LOI值为30.4%,达到UL-94 V-0级,总热释放量(THR)和热释放速率峰值(PHRR)显著降低,燃烧后形成了更加致密、稳定的膨胀炭层,优于两种阻燃剂单独使...  相似文献   

3.
以开环聚合的方法合成了聚二氯磷腈,通过一系列优化的合成取代工艺,成功批量化制备了高分子量氟化聚磷腈弹性体。其侧基结构主要是以氟代烷氧基为主,同时引入少量含双键基团的侧基结构以提供硫化交联点。研究结果表明:制备的氟化聚磷腈橡胶分子量达到38万,其拉伸强度可达8.4MPa,断裂伸长率162%;且具有优异的阻燃自熄性,其UL-94阻燃测试达到V-0级,极限氧指数(LOI)为59%,并具有很好的耐油性,在10号、15号液压油中150℃浸泡72h条件下的体积变化率均10%。  相似文献   

4.
基于磷-氢键与羰基加成反应采用"一锅法"合成3种含羟基的反应型磷系阻燃剂:2-(5,5-二甲基-2-氧代-1,3,2-二氧杂磷杂环己基)-2-丙醇(DMTO)、2-(5,5-二甲基-2-氧代-1,3,2-二氧杂磷杂环己基)-2-苯乙醇(RLGL)和2,4,8,10-四氧杂-3,9-二磷杂[5.5]十一烷-3,9-二氧-3,9-二异丙醇(DPDM)。以红外光谱、核磁共振、质谱及热重分析对其进行表征,进一步将DMTO,RLGL和DPDM以不同添加量对聚氨酯(PU)进行阻燃改性,研究化合物的构效关系。结果表明,3种阻燃剂对PU皆具有明显的促进成炭作用,随添加量的增加,极限氧指数(LOI)增长显著,其中PU-DMTO 10%的LOI值可达26%,使用量为5%时,阻燃PU的UL-94等级都可达V-0级。扫描电镜测试结果表明,其燃烧后残炭表面呈致密炭层,具有凝聚相阻燃特征。  相似文献   

5.
以9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物(DOPO)、衣康酸(ITA)及10-(2,5-二羟基苯基)-10-氢-9-氧杂-10-磷杂菲-10-氧化物(ODOPB)等为原料,制备了一种新型聚磷酸酯阻燃剂聚2-[(10-氢-9-氧杂-10-磷杂菲-10-氧化物)亚甲基]丁二酸-1-[2-(10-氢-9-氧杂-10-磷杂菲-10-氧化物)]对苯二酚酯(POBHOP)。将其应用于环氧树脂EP(E-51)中,制备EP/POBHOP阻燃复合材料。利用极限氧指数(LOI)、垂直燃烧(UL-94)、热重分析(TGA)、拉伸和冲击测试等方法研究了该阻燃复合材料的燃烧性能、热稳定性和力学性能。实验结果表明,加入5%POBHOP后,EP/POBHOP复合材料的LOI达到30.3%,UL-94为V-0级,TGA显示700℃下剩余残炭量达39.49%。力学性能测试结果显示,EP/POBHOP复合材料拉伸强度和断裂伸长率均出现先增后降现象,冲击强度略微下降。  相似文献   

6.
以聚苯氧基磷酸-2-10-氢-9-氧杂-磷杂菲基对苯二酚酯(POPP)为阻燃剂,对PC/ABS合金进行阻燃改性。通过极限氧指数(LOI)测试、垂直燃烧(UL-94)测试、热重分析(TGA)测试、锥形量热(CONE)测试和扫描电镜(SEM)测试等表征方法研究其阻燃性能。结果表明,当阻燃剂添加量为15%时可以达到UL94 V-0级,LOI值为21.1%;最大热释放速率(Pk-HRR)下降41.7%,热释放总量(THR)下降31.1%;TGA和SEM分析显示改性PC/ABS合金具有更好的成炭效果,燃烧后能促进表面生成致密多孔炭层,有效的隔绝氧气提高材料的阻燃性能。  相似文献   

7.
以六氯环三磷腈与1-氧基磷杂-4-羟甲基-2,6,7-三氧杂双环[2,2,2]辛烷(PEPA)为原料,合成出一种磷腈衍生物阻燃剂六(1-氧代-1-磷杂-2,6,7-三氧杂双环[2,2,2]辛烷-4-亚甲基)环三磷腈(PEPAP)。通过红外光谱和核磁共振氢谱表征了PEPAP的化学结构。熔融共混法构建PEPAP/聚丙烯(PP)阻燃体系并考察其热稳定性和阻燃性能。热重分析表明,PEPAP在N2中初始热分解温度为312℃,800℃时残炭率为34%。阻燃性能测试表明,当PEPAP质量分数为25%时体系的氧指数达29.4%,且体系能够通过UL94 V-0级。红外光谱和扫描电镜结果显示体系残炭炭层完整致密且含有磷酸酯类结构,表明PEPAP是固相阻燃机理。  相似文献   

8.
以9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物(DOPO)、磷腈为基础单元合成阻燃剂六(4-DOPO羟甲基苯氧基)环三磷(DOPOMPC),将其与聚磷酸铵(APP)复配添加至环氧树脂(EP)制备出阻燃复合材料(DOPOMPC/APP/EP)。为进一步提高阻燃环氧树脂的阻燃及力学性能,添加不同质量分数的蒙脱土(MMT)制出新型阻燃环氧树脂材料(DOPOMPC/APP/MMT/EP)。通过极限氧指数(LOI)、水平燃烧、锥形量热、扫描电子显微镜观察等方法研究了蒙脱土与DOPOMPC的协同效应。实验结果表明,EP4(10%DOPOMPC/10%APP/3%MMT/77%EP)各项燃烧参数得到了最佳改善,复合材料综合表现最优。其中LOI值达到38.2%;热释放速率峰值较未经MMT处理的阻燃复合材料EP1(10%DOPOMPC/10%APP/EP)下降了29.1%;比消光面积平均值和一氧化碳释放率平均值分别降低了72.7%和65.5%;火势增长指数、发烟指数和毒性气体生成速率指数较EP1降幅分别达到38.2%、13.1%和34.0%;拉伸强度、弯曲强度和冲击强度比EP1分别提高了25.4%、12.7%和1.97倍,呈现出良好的阻燃、抑烟、抑毒性能。炭层宏观和微观形貌表明,添加MMT的阻燃材料在燃烧初期能够形成更致密、坚硬的优质炭层。  相似文献   

9.
为了改善热塑性聚氨酯的阻燃性能,并尽量减小阻燃剂对其力学强度的影响,本文以三氯氧磷、季戊四醇(PER)、硫氰酸钾(KSCN)和1,3-丙二胺为原料合成了一种螺环状膨胀型高分子阻燃剂ISPDP,并采用核磁共振氢谱、红外光谱和凝胶渗透色谱对其结构进行了表征。热失重分析表明,ISPDP对热塑性聚氨酯具有明显促进成炭的作用。通过极限氧指数(LOI)和垂直燃烧(UL-94)对阻燃热塑性聚氨酯(ISPDPTPUs)体系进行燃烧测试,结果表明随着ISPDP添加量的增加,LOI增长显著,当达到最佳添加量15%时,LOI可以达到33,垂直燃烧等级为UL-94 V-0。扫描电镜对ISPDPTPUs燃烧后炭层表面研究结果显示,随着ISPDP添加量的增大,炭层表面变得更加致密。力学性能测试结果显示,ISPDP最优添加量15%时其拉伸强度略有增加,弹性模量大幅度增强,断裂伸长率仍可保持65%。  相似文献   

10.
采用两步法合成了一种具有磷腈和磷杂菲(DOPO)双效官能团的阻燃助剂六-(DOPO-羟甲基苯氧基)-环三磷腈(HAP-DOPO)。以六氯环三磷腈和对羟基苯甲醛为原料,通过亲核取代反应获得六-(4-醛基苯氧基)环三磷腈(HAP),进一步与9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物(DOPO)加成反应制得HAP-DOPO。采用红外光谱和核磁1HNMR证实了其结构。通过DSC和TGA测试,结果表明HAP-DOPO有明显的玻璃化转变温度(Tg=82℃),熔点(Tm)186℃,初始分解温度在200℃以上,在氮气氛围下600℃的残炭量达到了46.7%,成炭阻燃性能优良。  相似文献   

11.
凝固科学技术与材料   总被引:8,自引:0,他引:8  
从凝固科学与实践发展的角度介绍了当前凝固材料体系的基本框架和凝固科学主要发展阶段的基本理论。作为材料科学与工程的基本组成,凝固科学技术正在现代科学理论的基础上针对传统材料的改性提高和新材料的发展需求,以控形、控构、控性为目标开展优质铸件的定向、晶体生长、快凝、深过冷及各种新型和超常领域凝固过程的研究,并介绍了其中某些方面和展望了可能的发展趋势。  相似文献   

12.
13.
Production planning and scheduling are becoming the core of production management, which support the decision of a petrochemical company. The optimization of production planning and scheduling is attempted by every refinery because it gains additional profit and stabilizes the daily production. The optimization problem considered in industry and academic research is of different levels of realism and complexity, thus increasing the gap. Operation research with mathematical programming is a conventional approach used to address the planning and scheduling problem. Additionally, modeling the processes, objectives, and constraints and developing the optimization algorithms are significant for industry and research. This paper introduces the perspective of production planning and scheduling from the development viewpoint.  相似文献   

14.
单贺飞 《包装工程》2022,43(18):341-349
目的 探索江门世遗文化的传承、发展和转化的新思路,践行国家在《粤港澳大湾区发展规划》纲要中要求江门承担与港澳地区文化创意合作与开发任务的分工。方法 与澳门高校紧密合作,开展专业培训课程,以开平碉楼为例,从人文视角开展设计研究,梳理开平碉楼的文化脉络,把世遗文化的元素和其背后的文化融入文创产品中,提升文创产品的附加值,推动当地文创产业结构的变革。结果 两地高校构建了稳定的科研团队,开设长期有效的设计培训课程,与景区建立了研究协作关系,帮助景区构建了一套产销研的商业模式。结论 以跨区域高校合作为平台,以文创产品为抓手,依托江澳两地的资源优势,可以构建江门世遗文化全新的品牌形象,最终推动开平世遗文化的活化。  相似文献   

15.
Error and uncertainty in modeling and simulation   总被引:1,自引:0,他引:1  
This article develops a general framework for identifying error and uncertainty in computational simulations that deal with the numerical solution of a set of partial differential equations (PDEs). A comprehensive, new view of the general phases of modeling and simulation is proposed, consisting of the following phases: conceptual modeling of the physical system, mathematical modeling of the conceptual model, discretization and algorithm selection for the mathematical model, computer programming of the discrete model, numerical solution of the computer program model, and representation of the numerical solution. Our view incorporates the modeling and simulation phases that are recognized in the systems engineering and operations research communities, but it adds phases that are specific to the numerical solution of PDEs. In each of these phases, general sources of uncertainty, both aleatory and epistemic, and error are identified. Our general framework is applicable to any numerical discretization procedure for solving ODEs or PDEs. To demonstrate this framework, we describe a system-level example: the flight of an unguided, rocket-boosted, aircraft-launched missile. This example is discussed in detail at each of the six phases of modeling and simulation. Two alternative models of the flight dynamics are considered, along with aleatory uncertainty of the initial mass of the missile and epistemic uncertainty in the thrust of the rocket motor. We also investigate the interaction of modeling uncertainties and numerical integration error in the solution of the ordinary differential equations for the flight dynamics.  相似文献   

16.
17.
New measurements are reported for the density and viscosity of tetralin and trans-decalin. The density was determined from room temperature to 60°C for tetralin and to 95°C for trans-decalin. The kinematic viscosity was measured up to temperatures slightly above 100°C. Our results improve upon the values recommended by the American Petroleum Institute for these liquids.  相似文献   

18.
The national measurement system for photometric and radiometric quantities is presently based upon techniques that make these quantities traceable to a high-accuracy cryogenic radiometer. The redefinition of the candela in 1979 provided the opportunity for national measurement laboratories to base their photometric measurements on optical detector technology rather than on the emission from high-temperature blackbody optical sources. The ensuing technical developments of the past 20 years, including the significant improvements in cryogenic radiometer performance, have provided the opportunity to place the fundamental maintenance of photometric quantities upon absolute detector based technology as was allowed by the 1979 redefinition. Additionally, the development of improved photodetectors has had a significant impact on the methodology in most of the radiometric measurement areas. This paper will review the status of the NIST implementation of the technical changes mandated by the 1979 redefinition of the candela and its effect upon the maintenance and dissemination of optical radiation measurements.  相似文献   

19.
By making a step on one surface ( ) of a rectangular small paralellepiped copper crystal, dislocations could be created by the molecular dynamic method. The dislocation created was not a complete edge dislocation but a pair of Heidenreich-Shockley partial dislocations. Each time a dislocation was created, the stress on the surface was released. Small copper crystals having a notch were pulled (until fracture), compressed and buckled by use of the molecular dynamic method. An embedded atom potential was used to represent the interaction between atoms. Dislocations were created near the tip of the notch. A very sharp yield stress was observed. The results of high speed deformations of pure silicon small crystals using the molecular dynamics are presented. The results suggest that plastic deformation may be possible for the silicon with a high speed deformation even at room temperature. Another small size single crystal, the same size and the same surfaces, was compressed using molecular dynamic method. The surfaces are {110}, {112} and {111}. The compressed direction was [111]. It was found that silicon crystals are possible to be compressed with a high speed deformation. This may suggest that silicon may be plastically deformed with high speed deformation.  相似文献   

20.
罗林  黄志雄赵颖 《功能材料》2007,38(A09):3470-3472
SMC/BMC废弃物对工业及环境造成了很大影响,指出了SMC/BMC回收再利用的紧迫性。通过对目前国际上SMC/BMC回收再利用的3种典型途径优缺点的对比,参照国外SMC/BMC回收再利用的先进方法,对我国SMC/BMC回收再利用提供了可行的建议.  相似文献   

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