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1.
The effects of heat treatment below the melting point of 3,9‐bis{1,1‐dimethyl‐2[β‐(3‐tert‐butyl‐4‐hydroxy‐5‐methylphenyl)propionyloxy]ethyl}‐2,4,8,10‐tetraoxaspiro[5,5]‐undecane (AO‐80) on the thermal and dynamic mechanical properties and microstructure of chlorinated polyethylene (CPE) filled with vitrified AO‐80 particles were investigated. The initial AO‐80 was a complete crystal, whereas AO‐80 obtained by cooling from its melting state was amorphous. The vitrified AO‐80 particles could crystallize again in a CPE matrix by an annealing treatment, but this crystal was different from the initial AO‐80 in the microstructure. In addition, the incorporation of CPE chains caused a dramatic increase in the modulus. As a result, the AO‐80 crystal particles that contained some CPE chains acted as multifunctional crosslinks, and the CPE/AO‐80 hybrid was found to be a new type of elastomer. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 209–215, 2004  相似文献   

2.
The addition effects of organic small molecular substances N,N'-dicyclohexyl-benzothiazyl-2-sulfenamide(DZ)and 3,9-bis{1,1-dimethyl-2[β-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]ethyl}-2,4, 8, 10-tetraoxaspiro [5,5]-un-decane (AO-80) on the dynamic mechanical properties of chlorinated polyethylene (CPE), chlorinated polypropylene (CPP),acrylate rubber (ACM) and their blends were investigated. In the case of compatible systems such as CPE/DZ and ACM/AO-80, the height of the loss tangent (tanδ) peak of a matrix polymer (CPE or ACM) increases, and its peak position shifts to ahigher temperature with the addition of DZ or AO-80. By contrast, for incompatible CPE/AO-80, a novel transition appearedabove the glass transition temperature of CPE. This additional transition was assigned to dissociation of the intermolecularhydrogen bond between the α-hydrogen of CPE and the hydroxyl groups of AO-80 within the AO-80-rich domain. This willprovide a new concept for developing damping material. However, the minimum value between two tanδ peaks is lower. Itwas found that the temperature dependence of tanδ could be improved by adding chlorinated paraffin (CP) or ACM toCPE/AO-80. In addition, another ternary system of ACM/CPP with more AO-80 was found to be a very good self-adhesivedamping material because of the appearance of a novel transition due to an interfacial layer of ACM/CPP.  相似文献   

3.
Dynamic mechanical properties of chlorinated butyl rubber blends   总被引:1,自引:0,他引:1  
The binary blends are prepared by chlorinated butyl rubber (CIIR) and 3,9-bis[1,1-dimethyl-2{β-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy}ethyl]-2, 4, 8,10-tetraoxaspiro[5,5]-undecane (AO-80), which are investigated by dynamic mechanical analysis and thermal analysis. It is shown that CIIR/AO-80 blends clearly exhibit two kinds of relaxations, which are attributed to the relaxation of CIIR-rich matrix and AO-80-rich domains, respectively, and attenuated total reflection (ATR)-FTIR spectrum indicates that the existence of intermolecular hydrogen bonds between AO-80 and CIIR. When AO-80 is replaced by petroleum resins, only one loss peak appears, and the position of it is related to the softening point and the content of the petroleum resin. In order to regulate the damping property of CIIR/petroleum resin blend, the ternary blend of CIIR/petroleum resin/AO-80/is prepared and a second peak appears at higher temperature indicating that a good damping material is obtained.  相似文献   

4.
Dynamic mechanical properties and microstructure of an organic hybrid consisting of chlorinated polyethylene (CPE) and 3,9‐bis[1,1‐dimethyl‐2{β‐(3‐tert‐butyl4‐hydroxy‐5‐methylphenyl)propionyloxy}ethyl]‐2,4,8,10‐tetraoxaspiro[5,5]‐undecane (AO‐80) were investigated. The AO‐80 clearly exhibited two second‐order transitions at 6 and 69 °C in addition to the melting: the transition at lower temperature is assigned to the glass transition, and the transition at higher temperature is considered to be caused by the dissociation of hydrogen bond between the hydroxyl groups of AO‐80. When blending with CPE, part of AO‐80 molecules was dispersed into the CPE matrix, and most of them formed an AO‐80‐rich phase. As a result, a novel transition appeared above the glass‐transition temperature of the CPE matrix. It was assigned to the dissociation of the intermolecular hydrogen bond between the α‐hydrogen of CPE and the hydroxyl groups of AO‐80 within the AO‐80‐rich phase. Dynamic mechanical properties and microstructure of CPE/AO‐80 hybrid were controlled by the thermal treatment. It was found that the CPE/AO‐80 hybrid is a good damping material and shows a shape memory effect. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 2285–2295, 2000  相似文献   

5.
The influences of the molecular weight and chlorine content of chlorinated polyethylene (CPE) on the dynamic mechanical propertiesof an organic hybrid consisting of CPE and 3,9‐bis[1,1‐dimethyl‐2{β‐(3‐tert‐butyl‐4‐hydroxy‐5‐methylphenyl)propionyloxy}ethyl]‐2,4,8,10‐tetraoxaspiro[5,5]‐undecane (AO‐80) were investigated. All CPE/AO‐80 hybrids clearly exhibited two kinds of relaxations, and their magnitudes varied according to the molecular weight and chlorine content of CPE. This was due to a change in the ratio of AO‐80 molecules dispersed in the CPE‐rich domain and the AO‐80‐rich domain. A comparison of the jump intensity in differential scanning calorimetry curves with the maximum value of the second tan δ peak demonstrated that the second relaxation was caused by the dissociation of intermolecular hydrogen bonding within the AO‐80‐rich domain. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 2943–2953, 2000  相似文献   

6.
以H_2O_2为氧化剂,将一系列磷钨杂多酸类离子液体用于催化环戊烯(CPE)选择性氧化制备戊二醛(GA)反应,筛选出催化活性最高的催化剂为[π-C_5H_5NC_(16)H_(33)]_3PW_4O_(16).分别探讨了溶剂种类、用量、催化剂用量、H_2O_2用量、反应温度和反应时间等因素对反应的影响.确定了优化的反应条件:5 mL乙酸乙酯,n(Cat.)∶n(H_2O_2)∶n(CPE)=0.03∶50∶33,35℃,18 h,环戊烯的转化率达100%,戊二醛的选择性达87%.催化剂[π-C_5H_5NC_(16)H_(33)]_3PW_4O_(16)循环使用7次后,戊二醛的选择性仍保持在80%以上.  相似文献   

7.
采用氯化钾(KCl)和钠基普鲁士蓝(NPB)材料Na2-xMn[Fe(CN)6]z·yH2O为原料,通过离子交换法制备了掺钠钾基普鲁士蓝(NKPB)材料K1.9Na0.1Mn[Fe(CN)6]·0.4H2O。电化学测试表明,与用传统共沉淀法制备的钾基普鲁士蓝(KPB)材料K1.85Mn[Fe(CN)6]0.98□0.02·0.7H2O(□代表[Fe(CN)6]空位)相比,采用离子交换法制备的NKPB具有更高的容量(0.1C首次放电容量达136.3 mAh·g^-1)、较好的循环稳定性(0.5C经过100次循环,容量保持率为96.1%)和优异的倍率性能(5C和10C容量分别为87.6和68.4 mAh·g^-1)。NKPB优异的电化学性能与其高的钾含量、完整的晶体结构、钠离子掺杂、纳米级的颗粒尺寸,以及独特的开放框架结构有关。  相似文献   

8.
本工作用振簧仪,在-150—80℃范围内,测试了四氟乙烯-全氟4-甲基-3,6-二氧杂△~7辛基磺酰氟共聚物的动态力学性能。样品是含有不同侧基数目的部分结晶共聚物。观察到四个松弛过程,按温度下降次序记为α、γ_1-、γ_2-、γ_3-。α峰(室温附近)系玻璃化转变。γ_1峰(-50℃,~215Hz)为主链有阻碍的短链段分子运动。γ_2-峰(-60℃,~230Hz)为侧基的分子运动。γ_3-峰(-77℃,~260Hz)为的链段运动,并且γ_3-峰的强度随结晶度增加而增强。  相似文献   

9.
研究了水含量和聚合反应温度Tp 对MeOH BF3体系引发异丁烯 (IB)阳离子聚合反应的转化率、产物的分子量及分子量分布的影响 ,求出在不同水含量条件下的Tp 对聚合物分子量影响的数学方程及相应的聚合度活化能Ep ,以期对体系中存在的微量水加以充分利用 .结果表明 ,[H2 O]和Tp 两者共同影响IB阳离子聚合反应过程及产物的分子参数 .当Tp 由 - 10 0℃升高至 - 5 0℃时 ,聚合转化率先增加到一定值后再减小 ,在- 80℃~ - 70℃范围内出现峰值 .在 [H2 O]较低时 ,Tp 明显影响着聚合产物的分子量及分子量分布 ,Tp 越低 ,分子量越高 ,分子量分布越窄 ;在 [H2 O]较高时 ,Tp 对分子量的影响程度较小 ,说明此时水对聚合反应的影响更为突出 .体系中水含量增大对IB阳离子聚合反应呈现不利作用 ,当 [H2 O]由 1 5× 10 - 3mol L增加至 4 6×10 - 3mol L时 ,Ep 由 - 4 0kJ mol增大至 - 17kJ mol ,说明随着 [H2 O]增大 ,水的负面效应更加明显 ,既促进副反应 ,又阻碍链增长反应 ,增长活化能增大 ,聚合物分子量降低 ,分子量分布变宽 .水的负面作用也随着Tp 升高而变得明显 .  相似文献   

10.
A new polymeric iodoplumbate complex [Zn(DMF)6][Pb2I6] 1 has been prepared and characterized by elemental analysis and single-crystal X-ray analysis. Its structure contains infinite iodoplumbate chains constructed by the [PbI5] subunit. EHT crystal orbital calculation and the experimental results show that this material is an unconventional semiconductor and the electrical character is associated with its structural feature.  相似文献   

11.
FTIR研究不同固化程度SiO_2/酚醛杂化材料官能团的变化   总被引:1,自引:0,他引:1  
采用FTIR光谱吸收峰的波数位移、A/A1612表示的吸收强度和半峰宽Δ1/2(O—H)/Δ1/2(C C)表示的谱带宽度,比较不同固化程度SiO2/酚醛树脂杂化材料官能团的变化.在相同固化条件下(120℃,2 h),杂化材料的氢键作用比酚醛树脂的强得多,羟基含量更高,而且杂化材料发生邻位取代缩合反应的比例特别高.正是因为杂化材料中未反应的官能团多,作为底漆使用时能与面漆中的官能团反应,实现无层间界面交联,获得层间结合力.过固化过程(160℃,1 h)能够有效降低杂化材料中的羟基含量,但醚键含量比酚醛树脂的高得多,而且过固化过程中酚环主要发生对位取代缩合反应.杂化材料固化后的颜色比热固性酚醛树脂的淡得多,与热塑性酚醛树脂的相当.在相同氧化程度下,杂化材料中无游离酚,比酚醛树脂更环保.  相似文献   

12.
<正> 关于四氢呋喃(THF)活性聚合的研究文献上已有较多报道,而对共聚合的“活”性行为则研究甚少。THF与环氧丙烷(PO)共聚合时副反应较多,如生成环聚体、异构化等。这是否影响链的“活”性,是饶有兴趣的问题。特别是THF均聚醚在分子  相似文献   

13.
The crystal structure of 2-[N,N-dimethylamino)methyl]benzenetel-lurenyl chloride (2), a compound previously formulated as bis[[2-(N,N-dimethylamino)methyl]phenyl] ditelluride bis hydrochloride (1a), was determined. In the molecule 2, tellurium is bonded to the carbon of the phenyl group [2.120(3) Å], the nitrogen of the ortho dimethylamino substituent [2.362(3) Å], and the chlorine atom [2.536(1) Å]. There also is an intermolecular interaction of the tellurium atom with the phenyl ring of a neighbouring molecule [3.655(1) Å], resulting in the formation of zigzag chains along the b axis. The noncentrosymmetric space group of the crystal can be explained by the chiral surrounding of tellurium.  相似文献   

14.
甲基丙烯酸三乙基锡酯的聚合反应动力学的研究   总被引:1,自引:1,他引:1  
<正> 有机锡聚合物可以用于防污涂料,与低分子有机锡化合物相比,具有低环境污染、长效等特点。近年来,人们对有机锡单体的合成、纯化、聚合和共聚合进行了研究,但有关动力学的研究报道甚少,而甲基丙烯酸三乙基锡酯(TETM)的聚合动力学未见报道。  相似文献   

15.
The film formation process of micro-PS particles (diameter 742 nm) and nano-PS particles (diameter 29 nm) wasstudied by atomic force microscopy and differential scanning calorimetry. During a step heating process, the particles wereannealed for 0.5 h at each selected temperature. It was found that the deformation and interdiffusion temperatures of themicro-PS particles are ca. 120-130℃ and 140-150℃, that of the nano-PS particles are 90℃ and 100-110℃ respectively.The DSC traces of nano-PS particles showed that there was an exothermic peak near T_g after annealing for 0.5 h at theselected temperatures below 90℃; otherwise, the exothermic peak disappeared after annealing at 100℃ or above. Comparedwith the micro-PS pedicles, the sintering process of nano-PS particles occurs at much lower temperature determined by theconfined state of polymer chains with higher conformational energy in nano-particles, and completes in a much narrowertemperature range driven mainly by the larger total surface energy.  相似文献   

16.
The grafting of ethylene glycol dimethacrylate (EGDMA) onto silk in aqueous alcohol systems using potassiumpersulfate (KPS) in the presence of air was investigated. Effects of grafting conditions, such as concentrations of monomer,initiator and formic acid, temperature and time, on the graft yield were determined. The optimum graft conditions were foundto be: T = 80℃, t = 30 min, [KPS] = 1.85% [on the weight ofmonomer (owm)]; [formic acid] = 0.2% (V/V); [EGDMA] =80% [on the weight of fiber (owf)]. The activation energy of grafting at 50-80℃ was found to be 71.31 kJ/mol for EGDMA.Grafting equations were also evaluated. The graft yield value can be regulated by the concentration of monomer. The graftcopolymerization of EGDMA onto silk is effective in improving the crease-proofing of silk fabrics.  相似文献   

17.
有机生色团/SiO_2-TiO_2二阶非线性光学杂化材料的研究   总被引:3,自引:0,他引:3  
以分散橙-3(DO-3)与γ-缩水甘油氧与基三甲氧基硅烷(KH-560)反应 得到的功能性生色团ASD为前体,采用溶胶-凝胶(sol-gel)法使ASD与钛酸四正 丁酯在酸性条件下共水解缩合,合成了新型稳定的有机生色团/SiO_2-TiO_2杂化溶 胶,并对该溶胶体系的相图进行了研究。利用傅立叶红外(FTIR)、透射电镜( TEM)和X射线能量色散谱仪(EDS)研究了杂化溶胶形成过程中的络合机理及溶胶 形态。由一维刚性取向气体模型计算杂化材料膜的二阶非线性光学(NLO)系数X~ (2) is 1.43 * 10~(-7) esu。差示扫描量热法(DSC)测得杂化材料的玻璃化温度 可达196 ℃;用紫外-可见光谱对杂化膜在极化前后的取向及取向稳定性进行了研 究。  相似文献   

18.
研究了美索巴莫(MET)在离子液体1-苄基-3-甲基咪唑六氟磷酸盐[BnMIM]PF6修饰碳糊电极([BnMIM]PF6/CPE)上的电催化氧化行为和电化学动力学性质,并用循环伏安法(CV)、计时电流法(CA)测得MET在[BnMIM]PF6/CPE上的电极反应过程动力学参数。实验结果表明,MET在[BnMIM]PF6/CPE上发生了受扩散控制的不可逆电化学氧化过程。用方波伏安法(SWV)测得MET氧化峰电流(Ipa)与其浓度在3.0×10-5~1.0×10-2 mol?L-1范围内呈良好线性关系,检出限(S/N=3)为3.3×10-6 mol?L-1。同时运用SWV法对市售美索巴莫片进行电化学定量测定,RSD为1.5%~2.5%,加标回收率为98%~99%。  相似文献   

19.
余明新  康君辉  郑建鸿 《有机化学》2008,28(8):1393-1397
芳基伯胺与芳基溴在Pd(dba)2/P(t-Bu)3催化下于80 ℃甲苯溶液中反应生成芳基仲胺, 芳基仲胺再与3-溴苯并[de]蒽-7-酮在Pd(OAc)2/P(t-Bu)3催化下于120 ℃邻二甲苯溶液中反应生成苯并[de]蒽-7-酮类叔芳胺有机电致发光材料; 3-二苯基氨基苯并[de]蒽-7-酮与丙二腈反应生成2-(3-二苯基氨基)苯并[de]蒽-7-基亚基丙二腈. 产物的结构经1H NMR, 13C NMR, 13C (DEPT), HRMS光谱所证实. 用UV-Vis, PL, DSC测定了化合物的发光性能.  相似文献   

20.
Homo- and heterometallic 1D coordination polymers of transition metals (Co II, Mn II, Zn II) have been synthesized by an in-situ ligand generation route. Carboxylato-based complexes [Co(PhCOO)2]n (1 a, 1 b), [Co(p-MePhCOO)2]n (2), [ZnMn(PhCOO)4]n (3), and [CoZn(PhCOO)4]n (4) (PhCOOH=benzoic acid, p-MePhCOOH=p-methylbenzoic acid) have been characterized by chemical analysis, single-crystal X-ray diffraction, and magnetization measurements. The new complexes 2 and 3 crystallize in orthorhombic space groups Pnab and Pcab respectively. Their crystal structures consist of zigzag chains, with alternating M(II) centers in octahedral and tetrahedral positions, which are similar to those of 1 a and 1 b. Compound 4 crystallizes in monoclinic space group P2 1/c and comprises zigzag chains of M II ions in a tetrahedral coordination environment. Magnetic investigations reveal the existence of antiferromagnetic interactions between magnetic centers in the heterometallic complexes 3 and 4, while ferromagnetic interactions operate in homometallic compounds (1 a, 1 b, and 2). Compound 1 b orders ferromagnetically at TC=3.7 K whereas 1 a does not show any magnetic ordering down to 330 mK and displays typical single-chain magnet (SCM) behavior with slowing down of magnetization relaxation below 0.6 K. Single-crystal measurements reveal that the system is easily magnetized in the chain direction for 1 a whereas the chain direction coincides with the hard magnetic axis in 1 b. Despite important similarities, small differences in the molecular and crystal structures of these two compounds lead to this dramatic change in properties.  相似文献   

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