热分析中常见异常图谱浅析

热分析在化工领域的应用日趋广泛 ,热分析图谱是进行热分析的依据 ,经常困扰热分析工作者的常见异常热重 (TG)图谱、差式扫描量热法 (DSC)图谱 ,大致可归纳为热分析仪的启动、相变化、吸热放热变化等情况 ,本文针对不同情况进行分析 ,解释了异常图谱形成的可能原因和解决方法。     

热重仪在涂料分析中的应用

热分析方法在涂料中的应用越来越广泛.文章叙述热分析在涂料分析中的具体应用,并对涂料的热分解过程进行了分析,并利用热分析和红外光谱对涂料以及复杂样品的组分进行了定量和定性分析.     

多层热套式压力容器的热-应力耦合分析

针对石油化工行业中热套式压力容器壁厚增加和温差应力增大问题,提出了基于有限元热-应力耦合分析的方法.建立热套式压力容器筒体结构模型,采用序贯热-应力耦合解法,先进行热分析求解,然后将求解得到的热分析结果当作体载荷施加到结构上进行静力分析,得出热套式压力容器的径向应力、应变和环向应力、应变.     

差示扫描量热分析技术在粉末涂料中的应用

介绍了热分析技术及差示扫描量热分析技术（简称DSC）的发展。结合实际应用,阐述了粉末涂料中几个常用技术指标（Tg、熔点、软化点、结晶度）的物理意义及测定方法,详细探讨了差示扫描量热分析技术在粉末涂料固化行为方面的应用研究,分析讨论了影响检测结果的几个主要因素。     

热分析技术在涂料分析研究中的应用

介绍了近些年来国内外热分析技术在涂料分析研究中的应用进展。阐述了热分析技术在涂料成分和含量分析、固化、老化、热稳定性、热降解等方面的应用,最后展望了热分析技术在涂料分析研究的应用前景。     

应用热分析技术辨识建筑钢结构耐火涂料可行性研究

膨胀型耐火涂料有涂布厚度薄、重量轻、色彩美观、施工容易等优点,已成为建筑钢结构广泛使用的防火涂料之一.但钢材用耐火涂料(Fire Resistance Coating)外观方面与一般油漆涂料相近,使用者分辨不易,且易与不俱有防火时效的涂料造成混淆,影响防火安全.热分析技术是运用材料受热后分解,产生化学热反应,量测获得产品热重分析与热差分析的图谱.以热重分析和热差分析的技术进行测试,研究发现热分析的图谱,在相同材料有稳定的再现性,相异的涂料产品之间也有良好的鉴别力,以此技术作为材料产品质量管理具有可行性.     

热分析技术在矿物方面的应用

本文收集了国内外热分析技术在矿物方面应用的最新进展和动向，并结合笔者近年来的部分研究成果，用热分析与其它测试手段联用研究矿物的热学性质；ＤＴＡ研究矿物岩石成因、确定围岩的变质程度等方面进行了综述。     

热分析技术的应用

采用热重和差热分析法在氮气气氛下对硝酸铵、壬二酸、cuSO4 5H2O进行热分析实验。通过对实验过程和结果的分析,得到热分析技术可以应用于有机物纯度的测定、捕捉物质晶型转变以及热解机理的推断,已经成为化学领域一种重要的分析检测方法。     

热分析在煤燃烧和热解及气化动力学研究中的应用

论述了煤的燃烧、热解、气化反应动力学的常用的单一升温速率法、多重扫描速率法、动力学补偿效应以及分布活化能动力学模型等热分析研究方法，分析了现用热分析动力学方法的局限性；并对反应控制热分析、微热分析技术、微波热分析以及热分析技术与其他分析技术的联用，热分析技术间的联用等热分析新技术在煤的燃烧、热解、气化反应动力学研究上的应用进行了展望．     

热重分析用于测试烧蚀材料

介绍了四种聚合物和五种酚醛树脂在氮气中的热重分析结果，同时介绍了采用改性酚醛树脂的五种烧蚀试样的热重分析结果。说明了热重分析在表征烧蚀材料及其原料的热失重过程、结炭率及聚合物主链断裂分解活化能方面的应用。     

热分析技术在高分子材料研究中的应用

论述了热分析技术在高分子材料物理化学性质研究中的具体应用 ,如玻璃化转变温度、熔点、氧化诱导期、分解温度以及化学组成含量等 ,并对样品的分析条件进行了探讨     

Sonochemical preparation of palygorskite nanoparticles

Palygorskite nanoparticles were prepared by sonochemical reaction. The products were characterized by X-ray fluorescence analysis (XRF), X-ray powder diffraction (XRD), thermal gravimetry analysis (TGA), differential thermal analysis (DTA) and infrared spectroscopy. The morphology and size of the nanorods were observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM).     

Study on the Thermal Stabilization Effect of Polyamide on Polyoxymethylene

The thermal stabilization effect of polyamide (PA) on polyoxymethylene (POM) was studied by the isothermal weight loss analysis and thermogravimetric analysis (TGA), which shows that with the increase of PA content, the thermal weight loss and degradation rate decrease, the characteristic thermal degradation temperatures increase, and the thermal stability of POM can be improved remarkably. The nonisothermal degradation kinetics evaluated from TGA by the Coats-Redfern method shows that the PA-modified POM has higher activation energy than the virgin POM. The yellow index (YI), the melt index (MI), and the mechanical property measurements for both the virgin and the modified POM by multiple-processing further demonstrate that the PA applied in this study shows remarkable thermal stabilization effect on POM.     

Helical polyurethane-imide with optical activity based on binaphthyl units: preparation, characterization, and study of interchain hydrogen bonds

Helical polyurethane-imide with optical activity based on R-1,1′-binaphthyl-2′,2-diol (R-BINOL) and racemic polyurethane-imide (racemic-PUI) based on racemic 1,1′-binaphthyl-2′,2-diol (racemic-BINOL) were synthesized by hydrogen transfer addition polymerization procedure and characterized by ¹H NMR spectra, Fourier Transform Infrared Spectroscopy (FT-IR), thermal Fourier transform infrared spectroscopy (thermal FT-IR), X-ray diffraction (XRD), circular dichroism (CD) spectroscopy and thermogravimetric analysis (TGA). R-PUI exhibits the single-handed helical conformation and optical activity via CD spectra analysis. The optical rotation of R-PUI is +55.0°, which is larger than that of R-BINOL. The thermal stability of R-PUI is higher than that of racemic-PUI by TG analysis. According to the FT-IR and thermal FT-IR analysis, R-PUI with single-handed conformation possesses prominently interchain hydrogen bonds interactions, which plays an important role in thermal stability and optical activity.     

Curing and thermal behaviors of inorganic–organic hybrid polyarylacetylene resins with polyhedral oligomeric octa(propargylaminophenyl)silsesquioxane

Polyhedral oligomeric octa(propargylaminophenyl)silsesquioxane (OPAPS) was used to prepare composite resins with prepolyarylacetylene (prePAA). The curing and thermal behaviors of the PAA/OPAPS composites were studied through Fourier‐transform infrared (FTIR), X‐ray diffraction (XRD), differential scanning calorimetric (DSC), thermogravimetric (TGA), and scanning electron microscopic (SEM) analysis and by direct observation. The morphologies of the PAA/OPAPS resins proved that there was good compatibility between PAA and OPAPS. FTIR analysis indicated formation of a conjugated diene and aromatic ring groups in the thermal curing process of the resins. DSC analysis implied that the addition of OPAPS to prePAA could decrease the exothermic heat and widen the temperature range in the curing process of prePAA. According to TGA analysis, a 10 wt % addition of OPAPS to PAA can maintain the thermal stability of PAA in N₂ atmosphere and somewhat enhance the thermal‐oxidative stability. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

氧氟沙星的热稳定性及其热分解动力学

测定了在氮气气氛中第三代氟喹诺酮类药物氧氟沙星(OFLX)的热稳定性。用差示扫描量热法(DSC)、热重法(TG)和微分热重法(DTG),研究了药物氧氟沙星的热分解动力学。计算了动力学参数E、n、A,并结合量子有机化学计算的键长、原子静电荷参数研究了热分解机理,推断了热分解机理及药品贮存期。用热分析研究固体药物的热分解过程方法简便,结果可行。     

Thermal decomposition behavior of sericin cocoon

The behavior on thermal degradation of the sericin cocoon consisting of a sericin and a few fibroin has been examined by means of evolved gas analysis (EGA), evolved gas detection (EGD), and differential thermal analysis (DTA). The sericin cocoons produced from the silkworm (Nd, Nd-s/Nd-s,Nd-s/+) and sericin stripped from the silk gland in the silkworm show two endothermic peaks at 220°C and 270°C according to differential thermal analysis. From the x-ray diffraction pattern, dynamic mechanical measurement, and the thermal gravity analysis (TG), the former peak occurs by the scission of the structural state and the change from crystalline to amorphous. Moreover, at 220°C, the weight changes markedly, the yellowness index (L/b) measured by the color difference meter abruptly decreases, and the gas (CO₂), evolved from the sericin cocoon, shows increases above 200°C.     

Thermal characterization of high performance PBI and 6F polymers and their alloys

The effectiveness of thermal analysis as a technique for screening polymeric candidates for high temperature composite application is described. DSC, DMA, and TGA were employed to measure glass transition temperature, characterize blend phase morphology, and assess thermo-oxidative stability. The materials studied were polybenzimidazole (PBI), polyimide copolymer (6FCoPI), and blends of PBI with Ultem 1000? and 6FCoPI. The potential of misinterpretation of thermal analysis as the primary screening tool was also demonstrated. It was shown that if thermal analysis was used with insufficient understanding of the chemistry and physics of the materials under investigation, highly misleading conclusions may be derived.     

Study on lanthanum‐pentaerythritol alkoxide as a thermal stabilizer for rigid polyvinyl chloride

Lanthanum‐pentaerythritol (La‐PE) alkoxide, a polyol‐based metal alkoxide, had been synthesized and used as a thermal stabilizer for polyvinylchloride (PVC) . Thermogravimetric (TG), differential thermal analysis (DTG), mass spectrum (MS), and Fourier transform infrared (FTIR) spectroscopy were used to confirm the synthesis reaction. The thermal stability of rigid PVC stabilized with La‐PE was tested by means of the Congo Red test, conductivity test, thermal aging test, thermal gravimetric analysis (TGA), and UV‐visible (UV‐vis) spectroscopy. The results showed that addition of La‐PE could significantly prolong static stability time of PVC and increase the apparent activation energy for degradation reaction. The oven aging test showed that La‐PE could improve the initial color of PVC. Moreover, addition of La‐PE could significantly reduce the concentrations of the conjugated double bonds of PVC and reduce weight loss . The possible thermal stability mechanism had also been discussed. Besides having good ability to neutralize hydrochloric acid (HCl), La‐PE could substitute or inactivate the labile chlorine atoms in the PVC chains. J. VINYL ADDIT. TECHNOL., 23:55–61, 2017. © 2015 Society of Plastics Engineers     

Thermophysical properties of foliated graphite/nickel reinforced polyvinyl chloride nanocomposites

A novel, polymer‐based foliated graphite/nickel nanocomposites with high thermal conductivity, mechanical properties, and low dielectric constant was developed. The network structure of polyvinyl chloride (PVC) reinforced foliate graphite and nickel nanoparticles (GN) were tested in terms of X‐ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive x‐ray analysis (EDX), and thermal‐gravimetric analyses (TGA). Thermogravimetric analysis revealed a large improvement in the thermal stability of PVC/GN nanocomposites. Thermal conductivity and diffusivity of the composites increased with increasing GN content and temperature. The obtained experimental thermal conductivity result are compared with the existing theoretical models. The measured values of thermal conductivity were in excellent agreement with those calculated from the Agari model. In addition, specific heat, coefficient of thermal expansion (TEC), micro porosity, and crosslinking density (CLD) of composites were investigated. The mechanical properties such as tensile strength, tensile modulus, hardness, and elongation at break of the nanocomposites were improved with inclusion GN which is proportional to GN content. Finally, the dielectric properties of PVC/GN nanocomposites as a function of frequency have been investigated in details. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012