聚氨酯/纳米CaCO3复合材料的制备与性能研究

以聚四氢呋喃醚二醇-1000（PTMG）、甲苯-2，4-二异氰酸酯（TDI）、3，3-二氯-4，4-二苯基甲烷二胺（MOCA）为原料，采用预聚法合成聚氨酯弹性体，并选用纳米CaCO3颗粒对聚氨酯弹性体进行增强。结果表明，纳米CaCO3对聚氨酯弹性体的力学性能有一定的提高，并且在纳米CaCO3含量为1％时综合性能最好。     

Characterization of Ionic Conducting Cross-linked Polyether Electrolytes

An appropriate amount of toluene 2,4-diisocyanate（TDI） was added into polyether（[（CH2CH2O）13 CH2O]n/Li salt electrolyte to form a cross-linked network,with improving the film proces sability and thermal stability.The relation between the structure and ioinc conductive properties of the cross-lined polyether electrolytes was investigated by means of Fourier transform infra-red spectroscopy（FTIR）,differential scanning calorimetry（DSC）,mechanical property and AC impedance spectroscopy.The electrolytes system is found to have two glass transitions,and it is found that the two Tgs increase with increasing salt concentration.At the some Li salt concentration,the conductivity of cross-liked polyether/LiN（CF3SO2）2 complex system is higher than that of LiClo4,At EO/Li=25：1（mol ratio）,the former conductivity changes with temperature,while the later coincids with Arrhenius formula（σ=Ae^-Ea/RT）.The cross-linked polyether/LiN（CF3 SO2）2 electrolyte exhibits the maximum σ=10^-4.75S/cm at 30℃.     

Structural characteristics and properties of polyurethane modified TDE-85/MeTHPA epoxy resin with interpenetrating polymer networks

Diglycidyl-4,5-epoxycyclohexane-1,2-dicarboxylate（TDE-85）/methyl tetrahydrophthalic anhydride （MeTHPA） epoxy resin was modified with polyurethane（PU） and the interpenetrating polymer networks（IPNs） of PU-modified TDE-85/MeTHPA resin were prepared. The structural characteristics and properties of PU-modified TDE-85/MeTHPA resin were investigated by Fourier transform infrared（FTIR） spectrum,emission scanning electron microscopy（SEM） and thermogravimetry（TG）. The results indicate that epoxy polymer network （Ⅰ） and polyurethane polymer network （Ⅱ） of the modified resin can be obtained and the networks （Ⅰ） and （Ⅱ） interpenetrate and tangle highly each other at the phase interface. The micro morphology presents heterogeneous structure. The integrative properties of PU-modified TDE-85/MeTHPA epoxy resin are improved obviously. The PU-modified TDE-85/ MeTHPA resin’s tensile strength reaches 69.39 MPa,the impact strength reaches 23.56 kJ/m,the temperature for the system to lose 1% mass （t1%） is 300 ℃,and that for the system to lose 50% mass （t50%） is 378 ℃. Compared with those of TDE-85/MeTHPA resin,the tensile strength,impact strength,t1% and t50% of the PU-modified resin increases by 48%,115%,30 ℃,11 ℃,respectively. The PU-modified TDE-85/MeTHPA resin has the structure characteristics and properties of interpenetrating polymer networks.     

有效氯对氨纶损伤机理的探讨

对氨纶丝不耐有效氯的机理进行了研究，结果表明，聚酯型及聚醚型氨纶丝均易受有效氯损伤，而且后者更严重；２种氨纶丝经次氯酸钠溶液处理后再贮存，受损情况进一步加重，本文对所有结果作了合理的解释。     

聚氨酯系膜结构与性能的研究

采用湿法相转换成膜技术制备聚氨酯／聚乙二醇（PU／PEG）膜，聚氨酯／聚丙烯腈（PU／PAN），聚氨酯／醋酸纤维素（PU／CA）和聚氨酯／聚砜（PU／PSF）共混膜，利用膜性能测试仪，扫描电子显微镜等仪器对膜的结构与性能进行了研究，分析和讨论了铸膜液组成，制条件，成孔剂含量等对共混膜性能的影响。     

Synthesis and Characterization of Novel Polyarylene Sulfide

A novel polyarylene sulfide, polyarylene sulfide sulfone imide, was polymerized with a new monomer （Dichlorodiimide） and sodium sulfide by taking high temperature （200℃） N-methyl-2-pyrrolidinone （NMP） as solvent. The polymer was characterized by using conventional methods. Physical properties of the polymer, including thermal stability and solubility, were also studied. DSC and TG analyses reveal that the glass transition temperature T is equal to 252.4 ℃ and that the thermal decomposition temperature Td is equal to 484.9℃.     

丙烯酸酯类改性水性聚氨酯的合成与性能研究

以甲苯二异氰酸酯、聚醚二元醇、二羟甲基丙酸为主要原料通过逐步加成聚合合成水性聚氨酯(WPU)乳液.采用丙烯酸酯与水性聚氨酯乳液共聚制备聚氨酯--丙烯酸酯的复合乳液(PUA),研究了PUA复合乳液的合成工艺.对胶膜的耐水性、耐溶剂性和红外光谱分析等进行分析和讨论;结果表明,在PU链上成功地引入丙烯酸酯,经改性后的WPU耐水剂性明显提高,尤其是经BA改性后的吸水率有36.7%、降为4.31%,在耐溶剂方面也有明显的改善.     

水性聚氨酯涂饰剂的研制

以聚醚（聚酯）多元醇、多异氰酸酯、扩链剂和亲水扩链剂为主要原料制备了阴离子型水性聚氨酯,对制备过程中的一些影响因素进行了探讨,重点考察了扩链交联剂对水性聚氨酯性能的影响。     

Influence of different medium aging on advanced composite T300/5405

The aging properties of advanced composite T300/5405 which soaked in 15# hydraulic oil, 4010 lubricating oil, RP-3 kerosene and AHC-1 cleaner were studied. The absorption and mechanical properties of the composites were measured, and the scanning electron microscopy （SEIVO, dynamic mechanical analysis （DMA） and the infrared analysis （IR） were used to investigate the properties＇ changes of the composite. The aging mechanism of composite T300/5405 was also discussed. The experimental results show that the absorption of the composite in AHC-1 was the biggest, and the other three mediums had little effect on the composites. The mechanical properties declined in the aging. The composites have undergone chemical change in the test; Tg rose or declined atter the aging, and the AHC-1 cleaner and 4010 lubricating oil had the greatest influence on the Tg.     

Non-isothermal curing kinetics and thermal properties of benzoxazine-phenolic copolymers

Using novolac phenolic resin, aniline and formaldehyde as raw materials, benzoxazine-phenolic copolymers with different percentages of benzoxazine rings were prepared. FT-IR was adopted to characterize the molecular structure of the novolac-type phenolic resin and the benzoxazine-phenolic copolymer BP31. In order to understand the curing process of the copolymers, the curing behavior and curing kinetic characteristics were studied by differential scanning calorimetry (DSC), and the catalytical effect of phenolic hydroxyl on the curing behavior of copolymers was investigated. To investigate the thermal properties of this resin, the thermal degradation behaviors of the cured samples were studied by thermal gravimetric (TG) method, and glass-transition temperatures (T _g) of the cured copolymers were also evaluated by DSC. The dynamic Ozawa method was adopted to determine the kinetic parameters of the curing process as well. The activation energy is 78.8 kJ/mol and the reaction rate constant is in the range from 40.0 to 5.2 (K/min) ⁿ according to reaction temperatures. The Ozawa exponent decreases from 2.4 to 0.7 with the increase of reaction temperature, and curing mechanism is expounded briefly according to the results. TG result shows that the highest char yield of copolymers is 50.3%. The highest T _g of copolymers is 489 K, which is much higher than that of pure benzoxazine resin. Foundation item: Project (20050106) supported by the Key Science and Technology Item of Guangdong Province, China     

三溴苯基缩水甘油醚对聚醚聚氨酯的阻燃改性

在碱催化剂作用下,含有环氧基的阻燃剂三溴苯基缩水甘油醚（TBPGE）可以对聚醚聚氨酯进行阻燃和羟基化等功能化改性。产物结构分析结果表明,诸如n—C4H9Li等非亲核性强碱作为催化剂时,TBPGE在聚氨酯的氨基甲酸酯N—H基部位发生开环烷基化反应,产物中引入了阻燃结构单元,并产生了新生仲羟基,适用于多异氰酸酯硫化体系制造高性能阻燃PU材料。     

DMTDA在聚氨酯弹性体中的扩链性能研究

在聚氨酯弹性体加工成型中必须加入一种兼起扩链和交联作用的固化剂,一般使用的扩链剂是3,3’-二氯-4,4’-二氨基-二苯基甲烷（英文缩写为MOCA）,在本文的研究中,以自制的二甲硫基甲苯二氨（英文缩写为DMTDA）作为扩链固化剂,并考察了它的扩链性能,研究发现：对聚酯型聚氨酯弹性体而言,制备的DMTDA的扩链效果与国外同类产品ETHACURE300的扩链效果相当;而且在邵氏硬度方面,自制的DMTDA要优于ETHACURE300．结果表明：自制的DMTDA可以替代国外同类产品ETHACURE300在聚酯型聚氨酯弹性体中使用．     

Microstructure and microwave dielectric properties of lead borosilicate glass ceramics with Al2O3

The effects of Al₂O₃ addition on both the sintering behavior and microwave dielectric properties of PbO-B₂O₃-SiO₂ glass ceramics were investigated by Fourier transform infrared spectroscope (FTIR), differential thermal analysis (DTA), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results show that with the increase of Al₂O₃ content the bands assigned to [SiO₄] nearly disappear. Aluminum replaces silicon in the glass network, which is helpful for the formation of boron-oxygen rings. The increase of the transition temperature T _g and softening temperature T _f of PbO-B₂O₃-SiO₂ glass ceramics leads to the increase of liquid phase precipitation temperature and promotes the structure stability in the glasses, and consequently contributes to the decreasing trend of crystallization. Densification and dielectric constants increase with the increase of Al₂O₃ content, but the dielectric loss is worsened. By contrast, the 3% (mass fraction) Al₂O₃-doped glass ceramics sintered at 725 °C have better properties of density ρ=2.72 g/cm³, dielectric constant ɛ _r =6.78, dielectric loss tan δ=2.6×10⁻³ (measured at 9.8 GHz), which suggest that the glass ceramics can be applied in multilayer microwave devices requiring low sintering temperatures.     

Formation and thermal stability of Cu-Zr-Al-Er bulk metallic glasses with high glass-forming ability

The formation and thermal stabilities of Cu_46.25Zr_46.25-xAl_7.5Er_x, (x=0 to 8) bulk metallic glasses (BMGs) were investigated. The addition of a small amount of Er (2at%) for replacing Zr effectively improves the glass-forming ability of Cu_46.25Zr_46.25Al_7.5 alloy, and the glassy rod with a diameter of at least 12 mm can be formed. The glass transition temperature (T_g), temperature interval of supercooled liquid region ΔT_x (= T_x − T_g, and reduced glass transition temperature T_rg (=T_g/T₁) of Cu_46.25Zr_44.25Al_7.5Er₂ glassy alloy are 699 K, 62 K and 0.607, respectively.     

The Influence of Additives on Crystallization of Polyvinyl Chloride

Acetanilide, adipic acid and potassium hydrogen phthalate were chosen as nucleating agents of polyvinyl chloride（PVC）, and their effects on PVC crystallization were studied by differential scanning calorimetry, wide angle X-ray diffraction and fourier transform infrared spectroscopy. The experimental results indicate that all of the three additives are compatible with PVC to some extent, but adipic acid＇s compatibility with PVC is less satisfactory. The three additives can improve PVC crystallinity, and acetanilide can decrease PVC glass transition temperature（T）and narrow PVC melting range, while adipic acid and potassium hydrogen phthalate rise T of PVC and widen its melting range. All additives do not affect PVC crystal system and all g samples are in orthorhombic system. All additives can improve （200）, （110）, （210） and （201, 111） planes growing. Moreover, acetanilide and adipic acid can shrink PVC spacings and improve the crystal perfection of PVC, but potassium hydrogen phthalate swells spacings and reduces the perfection of PVC crystal.     

降解聚氨酯用微生物的驯化与筛选

以日本福井大学生物化学应用工学部保存的250个细菌菌株和70个真菌菌株作为菌源,分别提供与聚氨酯（PU）组成有关的3种有机物为碳源,经多代驯化后筛选出了对聚醚型聚氨酯有明显降解作用的8个菌株.文中就所用细菌和真菌对聚氨酯的降解性能进行了分析,并通过SDS-PAGE实验发现了菌体外酶存在的迹象.     

Melt synthesis and characterization of poly(L-lactic acid) chain linked by multifunctional epoxy compound

High molecular weight(Mw) poly(L-lactic acid)s(PLLAs) were synthesized using multifunctional epoxy compound(Joncryl-ADR4370) as chain extender. The products were characterized by gel permeation chromatography(GPC) and spectroscopy(¹HNMR and FTIR). The results indicated that the Mw of PLLA increased with the increasing of the ratio of epoxy compound and the extending of reaction time. The highest M _w of PLLA reached 360 000 g/mol when the ratio of epoxy compound was 1.5 wt%. However, the reactants turned to cross-linking when the ratio of epoxy compound was over 1.5 wt%. Differential scanning calorimetry(DSC) measurements demonstrated that the glass transition(T _g) and melting temperatures(T _m ) of products increased slightly as the increase of the molecular weight. Analysis of the hydrolytic degradation in vitro showed that the branched PLLA possessed the quicker degradability than that of the linear PLLA.     

Synthesis and Performance of Transparent Casting Polyurethane Resin

A series of transparent casting polyurethane resins (TCPU) were synthesized from cycloaliphatic diisocyaruae ( 1PDI or H12 MDI) , polyol, chain extender, crosslinking agents, catalyst and special aids (T),which were characterized by FTIR. The thermal stabilities of the obtained TCPU were examined by DSC and TGA , the glass transition temperature ( Tg ) was in the range of 95- 110 ℃ , the initial decomposition temperature (5% weight loss) was 250-265 ℃, and 10% weight loss at the temperature was in the range of 260-286℃ in nitrogen atmosphere. The morphologies of the fractured surfaces of TCPU were revealed by a scanning electron microscope (SEM). The crystalline-amorphous characters of TCPU were studied by WAXD, the result shows that TCPU possesses amorphous glassy characters. The optical properties of TCPU were studied by a UV7500 visible light absorbance measurement. All the samples exhibited excellent optical properties and possessed light transmittarwe in the range of 91%-93% .     

Effect of TBC plasticization on thin polycarbonate sheet

Tributyl citrate （TBC） plasticizer has been selected to prepare the novel plasticized PC under different time and temperature. The TBC plasticization effect on PC T, mechanical properties and morphology has been investigated by DMTA, DSC, tensile test and SEM. The results show that the TBC content in PC is controlled by plasticization time and temperature. The mass-loss test has conftnned a less lost rate of TBC in PC. The T declines gradually with increasing TBC content. The tensile modulus and strength of the plasticized PC also decrease with the increase of TBC content, and an approximate linear relationship is found to exist between the TBC content and the tensile modulus and strength. The SEM images show that significant changes have taken place on the surface and in the cross-section of plasticized thin PC sheet.     

Electronic transport properties of La2/3Ca1/3Mn0.98Cu0.02O3 sintered at different temperature

The sol-gel method was adopted to prepare series of La_2/3Ca_1/3Mn_0.98Cu_0.02O₃ samples sintered at different temperatures, and the structure of samples, high-temperature electrical conductive mechanism and electronic transport properties of double-peak resistance were investigated. X-ray diffraction pattern indicates that the samples are in perovskite structures and obey the Variable-Rang Hopping Mechanism of ρ=ρ ₀exp[(T ₀/T)^1/4] under high temperatures during the electrical conduction. In addition, based on the polycrystalline granular system surface and image, the reasonable explanation was given for the double-peak resistance phemomenon. Funded by the National Natural Science Foundation of China (No. 60471024)