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1.
Several kinds of novel chelating resins bearing the functional group of tartaric acid (TTA-FQ-12, TTA-FQ-23, and TTA-FQ-34) were synthesized by reacting epoxy maleic anhydride, which was prepared through the oxidization reaction of maleic anhydride by hydrogen peroxide, with phenol-formaldehyde resin containing polyamine (FQ resins series). The effects of such factors as reaction time, reaction temperature and pH value on the loading capacity of TTA in resins were investigated. The results showed that the optimum reaction conditions are as follows: time 9-12h; temperature 90-105℃;pH value 6-10. The loading capacities of TTA can reach 0.15, 0.14, and 0.11 mmol/g^-1 when the functional group of FQ resin was -OCH2CH2NHC2H4NH2, -O(CH2CH2NH)2C2H4NH2 and -O(CH2CH2NH)3C2H4NH2), respectively. The structures of resins were characterized by FTIR spectra. The primary study on the adsorption properties of the resins for metal ions showed that there are two kinds of adsorption mechanisms i.e. ion exchange and chelate in the adsorption process. TTA-FQ resins have much higher adsorption selectivity for Pb^2 and Zn^2 than for Cu^2 and Ni^2 . These resins can probably be used for separating Pb^2 or Zn^2 in the mixture of metal ions or for treating wastewater containing heavy metal ions.  相似文献   

2.
费昌沛  陈德恒 《化学学报》1983,41(4):364-370
大孔的苯乙烯-二乙烯苯共聚物经氯甲基化后,分别与乙酰丙酮镍、乙酰丙酮钠和四正丁基乙酰丙酮铵三种不同的乙酰丙酮盐反应,可制得聚3-(p-乙烯苄基)戊二酮-[2,4]。其中以由乙酰丙酮镍制得的聚合物最好,除二乙烯苯外,78%左右的苯环乙酰丙酮化了。该聚合物螯合Fe~(3 )和Ni~(2 )的能力与β-二酮基高聚物相仿或稍优。还比较了此类高聚物的物理机械性能。  相似文献   

3.
氨基吡啶树脂的合成及其对贵金属离子的吸附性   总被引:6,自引:1,他引:6  
合成了三种氨基吡啶树脂(APR)。功能基含量3.22—3.71mmol-NH-C_5H_4N/gAPR,吸附容量614.8—665mg Au(Ⅲ)/gAPR。摩尔络合比Au(Ⅲ)/-NH-C_5H_4N=1.0,Pt(Ⅳ)/-NH-C_5H_4N=0.48。选择吸附性Pt(Ⅳ)>Au(Ⅲ)>Cd~(2+)>Zn~(2+)>Pd(Ⅱ)>Mn~(2+)、Cu(2+)、Fe~(3+).吸附的Au(Ⅲ)可用2%硫脲水溶液定量地洗脱,再生的4-APR可重复使用。氨基吡啶树脂有应用开发前景。  相似文献   

4.
以Merrifield树脂为原料,家用微波炉为反应装置,在微波照射的相转移催化(MI-PTC)条件下,简便快速地合成了3种甲酰基功能化的交联聚苯乙烯树脂——对甲酰基苯氧基甲基树脂、对甲酰基-2-甲氧基苯氧基甲基树脂和对甲酰基-3-甲氧基苯氧基甲基树脂.在MI-PTC条件下,树脂制备过程所需的时间不超过1h,而传统加热制备方法则需要8h以上.实验中,微波输入功率为158W,反应过程用FTIR谱进行监测,碘化四丁基铵被考察为最好的相转移催化剂.该方法提供了一种反应条件温和、简便快速地制备功能化树脂的途径.  相似文献   

5.
Summary: In this study we report both the development of dithiocarbamate resins from the commercial hypercrosslinked resin MN-250 and the evaluation of the biocidal capacity of this material against E. coli ATCC25922 suspensions. The preparation of dithiocarbamate resins followed a synthetic pathway based on nitration of resins, reduction of nitro groups and reaction with CS2 in an alkaline medium. The biocidal capacity was evaluated by means of elution of E. coli suspensions (103–107 cells/mL) through columns containing the resin and plating on LB nutrient medium solidified with Bacto agar. We can conclude that hypercrosslinked resins with dithiocarbamate groups have potential biocidal action.  相似文献   

6.
Phenol-urea-formaldehyde (PUF) resins with different catalysts [calcium oxide (CaO), sodium carbonate (Na2CO3), zinc oxide (ZnO), and magnesium oxide (MgO)] were prepared to accelerate the cure of the resin at low temperature. The cure-acceleration effects of catalysts on chemical structure and cure characteristics of PUF resins were investigated by using both liquid 13C nuclear magnetic resonance (NMR) and differential scanning calorimetry (DSC). The liquid 13C NMR analysis indicated that the catalyst such as CaO seemed to present a retarded effect on the polycondensation reaction of phenolic components with urea units, while the Na2CO3 appeared to promote the self-condensation reaction of phenolic methylol groups at para position toward the formation of para-para methylene linkage. Both ZnO and MgO in PUF resins promoted self-condensation reaction of para methylol groups and condensation reaction of ortho methylol groups with para methylol groups. The catalysts such as Na2CO3, ZnO, and MgO can make PUF resins cure at a low temperature. Among these catalysts, the MgO had the most significant accelerating effect on polycondensation and cure reaction of PUF resin.  相似文献   

7.
由聚环硫氟丙烷与多乙烯多胺反应制得的聚合物(PB)再与环硫丙烷反应,合成了四种以聚硫醚为主链的异丙巯基胺树脂(PBM_1-4)。树脂对Au~(3+)、Pd~(2+)、Pt~(4+)、Ag~+和Hg~(2+)等离子具有强的吸附能力,对Cu~(2+)次之,对Zn~(2+)和Pb~(2+)很弱。树脂对贵金属具有高的选择性,能从含Au~(3+)、Cr~(3+)、Co~(2+)、Ni~(2+)、Cu~(2+)、Mn~(2+)、Zn~(2+)和Fe~(3+)的溶液中定量吸附Au~(3+)而不吸附其它离子。  相似文献   

8.
通过酚醛树脂羟基活性基团与6-氯-5,12-萘并萘醌(1)接枝反应,制备了3种有光致变色性的酚醛树脂:萘并萘醌酚醛树脂(2),甲基萘并萘醌酚醛树脂(3)和氯代萘并萘醌酚醛树脂(4).在四氢呋喃(THF)溶液中,3种光致变色聚合物有与6-苯氧基-5,12-萘并萘醌相似的光致变色行为.同时,发现聚合物骨架上的取代基对聚合物的变色速度影响较小,聚合物的平均分子量影响聚合物的变色速度.  相似文献   

9.
A novel toughened cyanate ester (CE) resin with good dielectric properties and thermal stability was developed by copolymerizing 2,2′‐bis(4‐cyanatophenyl)iso‐propylidene (BCE) with a combined modifier (HBPSiEP) made up of hyperbranched polysiloxane (HBPSi) and epoxy (EP) resin. HBPSi was synthesized through the hydrolysis of 3‐(trimethoxysilyl)propyl methacrylate. The effect of differing stoichiometries of HBPSiEP on the curing characteristics and performance of BCE resin is discussed. Results show that the incorporation of HBPSiEP can not only effectively promote the curing reaction of BCE, but can also significantly improve the toughness of the cured BCE resin. In addition, the toughening effect of HBPSiEP is greater than single EP resin. For example, the impact strength of modified BCE resin with 30 wt% of HBPSiEP is 23.3 KJ/m2, which is more than 2.5 times of that of pure BCE resin, while the maximum impact strength of EP/BCE resin is about 2 times of pure BCE resin. It is worthy to note that HBPSiEP/BCE resins also exhibit improved thermal stability, dielectric properties, and flame retardancy, suggesting that the novel toughened CE resins have great potentiality to be used as a matrix for advanced functional composites or electronic packing resins. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

10.
A range of PS-DVB resins were prepared by suspension polymerization with styrene, p-chloromethyl styrene, and DVB. Yields of polymerization increased (from 40% to almost 80%) with increasing cross-linking. The beads exhibited the expected swelling characteristics, with the 0.3% resin swelling to almost 9 times its dry volume in CHCl3. Kinetics of cleavage of the dye Methyl Red from the range of Rink linked resins showed rate enhancements of up to 500% between the 6.0 and the 0.3% cross-linked resins. Total synthesis of Kawaguchipeptin B was carried out on the resins, and their performance during the syntheses was investigated. Contrary to expectations, the purities of the cyclic peptide product increased with increasing resin cross-linking doubling from the 0.3-6.0% resin. A Suzuki reaction showed the half-lives of reaction increased with increasing resin cross-linking with an 11-fold increase in half-life between the 0.3-2.7% resin. Surprisingly, we observed very little reaction in the case of the 3.0 and 6.0% cross-linked resins.  相似文献   

11.
Peng Zhao 《Tetrahedron letters》2008,49(18):2951-2955
A new SASRIN resin derivative, SASRIN-TOPCAT resin, was synthesized by the reaction of SASRIN resin with 2-thiopyridyl chloroformate. The new resin can be used for the loading of alcohols and thiols under neutral conditions, and the release of alcohol from the resin is achieved by the treatment of 1% TFA in CH2Cl2 for 15-60 min. Compared to the other reported resins, SASRIN-TOPCAT resin is more suitable for the loading of alcohols in solid-phase organic synthesis.  相似文献   

12.
2-Aminobenzoxazole and a series of its N-substituted derivatives were prepared by the reaction of potassium benzoxazole-2-sulfonate with ammonia and various amines; some 6-nitro- and 6-acetamido-2-aminobenzoxazoles were also obtained. The reaction of 6-nitro-2-mercaptobenzoxazole with heterocyclic amines involves the initial formation of salt-like compounds with the mercapto-group, with subsequent elimination of hydrogen sulfide. Nitration of 2-aminobenzoxazole yields a mixture of 6-nitro-2-aminobenzoxazole and 6-nitro-2-nitraminobenzoxazole.For Part X see [6].  相似文献   

13.
在微波照射的相转移催化(MI-PTC)条件下,3种甲酰基功能化的交联聚苯乙烯树脂——对甲酰基苯氧基甲基树脂、对甲酰基-2-甲氧基苯氧基甲基树脂和对甲酰基-3-甲氧基苯氧基甲基树脂固载的甲酰基被NaBH4还原,得到相应的3种苄羟基功能化的树脂——Wang树脂、Sasrin树脂和新型的对苄羟基-3-甲氧基苯氧基甲基树脂.考察了溶剂、相转移催化剂等因素对反应的影响,优化的反应介质为THF/H2O混合溶剂,相转移催化剂为苄基三羟乙基氯化铵(BTHAC).然而,在传统加热和微波辐射条件下,最有效混合溶剂的配比有所不同.在水浴加热条件下,最有效的反应溶剂为12 mL THF+3 mL H2O;而在微波加热的条件下,最有效的反应溶剂却是3 mL THF+12 mL H2O.在优化的溶剂、催化剂条件下,微波功率为60 W时,高分子固载的甲酰基30 min之内几乎被定量地还原成羟基.与传统加热方式比较,MI-PTC还原聚苯乙烯固载甲酰基可以大大缩短反应时间,提高反应效率,是一种进行高分子化合物官能团转化的良好方法.  相似文献   

14.
一种可循环使用的固相试剂:N-烷基-N-酰基磺酰胺聚苯乙烯基微球(5), 通过对聚苯乙烯磺酰氯微球树脂进行两步功能基化的修饰反应来制备. 制备过程如下:聚苯磺酰氯树脂(1)与伯胺(2)反应得到聚苯乙烯基N-烷基磺酰胺树脂(3), 树脂3用酰氯(4)或酸酐酰化得到N-烷基-N-酰基磺酰胺聚苯乙烯基树脂(5). 酰化的树脂5作为酰基转移试剂与亲核试剂胺反应得到二级酰胺. 根据5上取代基对酰胺生成的程度的影响结果表明, 烷基R1和酰基(R2CO)对酰基转移反应活性的大小依次分别为:苯基>苄基>甲基>正丁基>>H和对硝基苯甲酰基(苯甲酰基>乙酰基. 胺的亲核能力对酰胺的收率也有一定的影响. N-苯基-N-苯甲酰基磺酰胺树脂重复使用3次没有发现活性降低.  相似文献   

15.
The most acceptable method for preparing glycerophosphocholine is to hydrolyse the natural phosphatidylcholine and use the quaternary ammonium base resin, as a promising heterogeneous catalyst can simplify the craft and minimise the problems existing in the homogeneous catalytic process. However, most of the resins reported in the literature are commercial trimethyl benzyl ammonium base resins and the application of other longer carbon-chain quaternary ammonium resins has not been reported. In the present work, a series of quaternary ammonium base resins were prepared from chloromethyl polystyrene microspheres and different tertiary amines and were used to prepare glycerophosphocholine from natural phosphatidylcholine. The factors affecting the exchange capacity and activity of the resin were investigated. The results showed that the resin possessed a better activity and stability under the following conditions: 1,4-dioxane as solvent, triethylamine as amination agent, reaction temperature of 60°C and amination time of 3 h; it was then used in the methanolysis of phosphatidylcholine by ultrasound-assisted reaction at ambient temperature, with the conversion of phosphatidylcholine attaining 97 % after 4 h. The catalyst was easy to separate from the reaction mixture and could also be readily available for repeat use; the activity and stability were largely consistent after six repeat uses.  相似文献   

16.
The liquid oxygen compatible epoxy resin was obtained by the polycondensation between tetrabromobisphenol A and neat epoxy resins. The results of liquid oxygen impact test indicated that the synthetic epoxy resins were compatible with liquid oxygen. The relationship between impact reaction sensitivity (IRS) and flame retardancy were studied by liquid oxygen impact test and limiting oxygen index test. The results showed that the flame‐retardant modification of epoxy resin was valuable to reduce the IRS. The thermal gravimetric analysis results indicated that the Br · radical was quickly released in relatively low temperature (approximately 370°C) for compatible epoxy resin. The Br · radical was a key factor to promote the epoxy resin compatible with the liquid oxygen. The X‐ray photoelectron spectroscopy was used to survey the distribution of functional groups on the surface of samples before and after impact. The results showed that the oxidation reaction and carbonization process may occur on the surface of samples after impact. The liquid oxygen compatibility mechanism is proposed in this paper. The bromine‐containing epoxy resin has the potential to be the material used in liquid oxygen tank. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

17.
Previously, we have reported the development and application of self-indicating resins (SIR), materials which can indicate presence or absence of amines in the reaction solution by the conspicuous color change of a phenolsulfophthalein type dye immobilized on resin beads [2a]. Although the functionality necessary for attaching the dye to the resins could be readily introduced by the Suzuki-Miyaura coupling during the synthesis of the SIR 1, this approach was only applicable to the dyes containing suitable functionality for the cross-coupling reaction. In this article we describe a new approach of immobilizing the indicating dyes onto the resin support. The dyes suitable for loading onto aminomethyl polystyrene (PS) resin were prepared by Friedel-Crafts reaction of 2-sulfoterephthalic anhydride with a wide range of phenols. Using this new route, the SIR 6c was readily prepared in >100g quantities. Use of the SIR 6c in the synthesis of a 144 member urea library was demonstrated and the SIR successfully indicated the endpoint of the reaction between amines and isocyanates.  相似文献   

18.
硼酸与甲阶酚醛树脂的配位反应及配合物的结构   总被引:3,自引:0,他引:3  
本文通过对溶液pH值的测定和外光谱分析,研究了硼酸与甲阶酚醛树脂的配位反应。结果表明:在室温下硼酸能与甲阶酚醛树脂中的羟基发生配位反应,并产生H^ 使溶液的pH值降低;溶液的酸性强弱与甲阶酚醛树脂中的羟甲基含量和硼酸的用量有关;硼酸以硼酸根离子的形式与树脂中的酚羟基和邻位羟甲基发生配位反应,形成了一个含有两个氧原子和一个硼原子的六元环,使甲阶酚醛树脂发生交联。  相似文献   

19.
The mechanism of the thickening reaction between alkaline earth metal oxides and acid group-terminated polyester resins was studied. The thickening can occur either by the increase in molecular weight of the resin through neutral salt formation or by complex formation between the basic salt and carbonyl oxygens. Simultaneous analysis of reacted resins for moisture content by near infrared spectroscopy and metal content by atomic spectroscopy was carried out to differentiate between the two possibilities. It was established that the amount of basic salt present in the reaction mixtures was small and hence the thickening appears to be due to neutral salt formation. The neutral salt formation reaction, being similar to condensation polymerization, could be modelled to predict the course of the thickening process as a function of time. A model proposed hypothesizes the thickening process to be heterogeneous in nature and to occur in a sequence of three steps: diffusion of metal oxide into the resin, reaction of the dissolved metal oxide with the resin to form the basic salt, and the further reaction of the basic salt with the resin to form the neutral salt. The model predicts all the observed features of the thickening process qualitatively. Further, quantitative agreement was obtained between experimental data and the theoretical predictions of plateau viscosities and in several aspects of the kinetics of the thickening process.  相似文献   

20.
Melamine formaldehyde resins (MFR) are well known resins in the wood board and paper coating market. Etherified MFR's are applied as crosslinkers in the automotive coating industry. In Europe the growth of the market and the research activities are relatively small. On the other side in comparison to other polymers outstanding properties are possible to realize. So the development of new melamine ether resins (MER) was started. MER is a partly methylolated and fully etherified resin with a highly stable “thermoplastic” processing range. The MER's themselves are transparent granulates with enough stability for storage and transport. The crosslinking reaction can be started either by thermal or acidic catalytic activation, without losses of formaldehyde. Transetherifications with oligomeric diols can lead to more elastic and higher molecular melamine polyether resin (MPER) structures. The reaction mechanism and the crosslinking kinetics of the partly methylolated melamine ethers of methanol in comparison to the fully methylolated hexamethylol melamine ether will be discussed in this paper.  相似文献   

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