Three poly(2,5 dialkoxyl phenelene vinylene) derivatives were synthesized from 1,4 dialkoxyl benzene and 1,2 dibromoethane by Friedel Crafts reaction followed by dehydrogenation. Their molecular weights are determined...Three poly(2,5 dialkoxyl phenelene vinylene) derivatives were synthesized from 1,4 dialkoxyl benzene and 1,2 dibromoethane by Friedel Crafts reaction followed by dehydrogenation. Their molecular weights are determined by gel permeation chromotography and structures characterized by IR, 1H NMR and UV Vis spectroscopy . All of the polymers obtained are constructed through a great number of π conjugated bonds.展开更多
Poly(2-methoxy-5-(2′-ethylhexyloxy)- p -phenylenevinylene) (MEH-PPV) has been prepared by a liquid/solid two-phase reaction.The liquid phase is tetrahydrofuran containing 1,4-bis(chloromethyl)-2-methoxyl-5-(2′-ethyl...Poly(2-methoxy-5-(2′-ethylhexyloxy)- p -phenylenevinylene) (MEH-PPV) has been prepared by a liquid/solid two-phase reaction.The liquid phase is tetrahydrofuran containing 1,4-bis(chloromethyl)-2-methoxyl-5-(2′-ethylhexyloxy) benzene as the monomer and a certain amount of tetrabutylammonium bromide (TBAB) as phase transfer catalyst (PTC).The solid phase is potassium hydroxide particles with diameters smaller than 0 5 mm.Gelation was found in the polymerization processes.As a result,MEH-PPV is partly soluble because of its large molar mass.Soluble MEH-PPV was obtained by using bromomethylbenzene as retardant regent.The molar mass of soluble MEH-PPV was measured to be 6 4×10 4g/mol.The Structure of polymer was identified by IR,Raman,UV/vis and PL spectra.A thin compact film of MEH-PPV can be formed by spin-coating and it emit a yellow light.展开更多
文摘Three poly(2,5 dialkoxyl phenelene vinylene) derivatives were synthesized from 1,4 dialkoxyl benzene and 1,2 dibromoethane by Friedel Crafts reaction followed by dehydrogenation. Their molecular weights are determined by gel permeation chromotography and structures characterized by IR, 1H NMR and UV Vis spectroscopy . All of the polymers obtained are constructed through a great number of π conjugated bonds.
文摘Poly(2-methoxy-5-(2′-ethylhexyloxy)- p -phenylenevinylene) (MEH-PPV) has been prepared by a liquid/solid two-phase reaction.The liquid phase is tetrahydrofuran containing 1,4-bis(chloromethyl)-2-methoxyl-5-(2′-ethylhexyloxy) benzene as the monomer and a certain amount of tetrabutylammonium bromide (TBAB) as phase transfer catalyst (PTC).The solid phase is potassium hydroxide particles with diameters smaller than 0 5 mm.Gelation was found in the polymerization processes.As a result,MEH-PPV is partly soluble because of its large molar mass.Soluble MEH-PPV was obtained by using bromomethylbenzene as retardant regent.The molar mass of soluble MEH-PPV was measured to be 6 4×10 4g/mol.The Structure of polymer was identified by IR,Raman,UV/vis and PL spectra.A thin compact film of MEH-PPV can be formed by spin-coating and it emit a yellow light.
文摘以鸡腿蘑发酵液中分离获得的具有抑制蛋白质非酶糖基化活性的新物质4,5-二羟基-2-甲氧基苯甲醛为对象,建立检测鸡腿蘑发酵液中该物质的高效液相色谱方法.其回归方程为Y=675.42X-943.39(r2=0.999 0),线性范围为1.23～123 mg/L.该方法的日内和日间精度分别为1.5%～5.6%,2.5%～4.6%,回收率为93.8%～96.6%.该方法能够在20 m in内完成一次分析,具有快速、准确、可靠的特点.
