基于氢键的侧链型超分子电光聚合物的制备与表征

设计并制备了一种基于氢键的侧链型超分子聚乙烯基吡啶电光聚合物,非线性发色团与聚合物主链之间的氢键作用经红外光谱进行表征。采用氢键将发色团挂接到聚合物,可一定程度地抑制发色团分子的聚集,防止宏观相分离,实现发色团的高浓度掺杂。同时,利用超分子氢键作用挂接也可在一定程度上抑制发色团间的偶极-偶极相互作用力,测得此体系极化电光聚合物薄膜的最大电光系数为17.6 pm/V。     

一种新型二阶非线性光学功能分子及其交联聚氨酯材料的合成

合成了新型的含有偶氮和噻吩环的二阶非线性光学功能分子, 用红外光谱、紫外光谱、核磁共振和质谱确定了其结构; 制备了含有该功能分子的两种交联型聚氨酯聚合物薄膜, 当测量波长为1 064 nm时,  用Marker条纹法测得的二阶非线性光学系数d33值分别为80.6 pm/V(发色团的数密度为0.91×1020 Molecules/cm3)和20.1 pm/V(发色团的数密度为2.21×1020 Molecules/cm3); 聚合物Ⅱ的取向热稳定性达到了152 ℃.     

高热稳定性和可逆交联性质的含新型偶氮发色团电光聚合物的研究

制备了两种新型的分别含有以三苯胺为电子给体的偶氮类发色团作为特征活性官能团和3-呋喃甲酸及受保护的马来酰亚胺的可交联型聚合物体系.通过研究表明利用该制备方法,发色团在聚合物中的含量得到了极大的提高,分别达到32 .1 %( NLO1-P1)和44 .4 %( NLO1-P2) .该聚合物体系以"Diels-Alder"[4 +2]环加成反应作为其交联特征,具有高温非交联、低温交联的特点,其过程与以往的热交联型聚合物相反,可解决传统电光交联聚合物中存在的热交联对极化效率影响的问题并用热失重分析法(TGA)和差示扫描量热法(DSC)分析了这一过程.此外DA交联型聚合物,不需要引入额外的助交联剂,克服了传统热交联聚合物分离难的问题,最大程度的保证了材料的纯度.     

枝化二阶非线性发色团分子的合成及在聚合物体系中的电光性能

设计合成了一类以2-二氰基次甲基-3-氰基-4,5,5-三甲基-2,5-二氢呋喃(TCF)为受体、己氧基取代噻吩为π电子桥的新型有机非线性光学化合物, 并利用紫外光谱、红外光谱、核磁共振以及质谱对化合物分子结构进行了鉴定, 同时对此类化合物在有机聚合物体系中的电光性能进行了表征和研究. 结果发现, 该类发色团分子与聚合物相容性好, 电光活性高, 并且随着发色团分子在聚合物体系中浓度的升高, 聚合物体系的宏观电光活性也有所提高, 甚至当发色团的掺杂质量分数高达47.2%时, 体系的电光活性仍呈上升趋势, 显示了该发色团的静电相互作用得到了明显抑制. 此时测得聚合物体系的电光系数为30 pm/V(1310 nm).     

可交联的PMMA型和PS型高热稳定性二阶非线性光学材料的合成与表征

采用封管反应的方法,以较高产率(80%以上)合成了一系列含环氧基团的可交联PMMA型和PS型极化聚合物材料,该材料具有很好的成膜性.用DSC和T_gA等方法研究了聚合物固化前后的热性能,结果表明,由于聚合物在极化后期经热固化使引入的环氧基团开环交联,聚合物的玻璃化转变温度(T_g)较固化前明显提高30～50K.同时,固化后的聚合物具有较高的热分解温度(T_d>543K).对聚合物的二阶非线性光学性质的测试结果表明,在室温下放置100h后,聚合物的电光系数r₃₃值均保持在初始值的75%以上.这是由于环氧基团的开环使固化后的聚合物本身产生一定程度的交联,导致取向后的发色团被聚合物的交联网禁锢而不易弛豫,从而使这类PMMA型和PS型二阶非线性聚合物材料的热稳定性能得以提高.     

枝化苯胺-吡咯啉发色团的合成及其电光性质的研究

为了减少发色团偶极相互作用,在二阶非线性发色团苯胺-吡咯啉分子的受体吡咯啉的N原子上分别接入三种不同的枝化基团,将其高μβ值有效转化为高电光性能.研究了三种枝化发色团的电光性能和相关化学物理性质,比较了不同枝化基团对发色团的综合性能的影响.结果表明,枝化基团的接入引起发色团分子的紫外吸收红移,枝化基团修饰的发色团,改善了苯胺-吡咯啉发色团分子与聚碳酸酯(APC)的相容性,并明显减少了发色团偶极静电相互作用,提高了发色团在电场下的极化效率,使其在聚碳酸酯(APC)薄膜中的极化序列参数可高达44%.并测得当枝化发色团在APC中掺杂的含量为9%时,聚合物体系电光系数高达75 pm/V(1315 nm激光测定).     

用核磁共振方法研究弱交联高分子体系的微观运动状态及微观结构特征

用核磁共振１３Ｃ自旋－自旋弛豫时间Ｔ２表征了以离子微区为表观交联点的以甲基丙烯酸丁酯－丙烯酸共聚物为基础的弱交联高分子体系的微观链运动特征，及体系中溶剂分子的运动特征，结果表明：聚合物主链表现为快、慢两种运动状态，聚合物体系存在多相结构；溶剂分子也表现出两种不同的运动状态，从而间接反应了聚合物体系的微观结构。     

一步法合成高T_g可溶含偶氮三嗪发色团的新型侧链含氟聚酰亚胺

采用一步法合成了一系列侧链含偶氮三嗪发色团的新型含氟聚酰亚胺FPI(x),并研究其溶解性能、热性能以及光学性能.该系列聚酰亚胺具有优良的溶解性能,不仅溶于NMP,DMAc,DMF,DMSO等强极性非质子性溶剂,而且还溶于THF和乙二醇单甲醚等低沸点溶剂.FPI(x)系列共聚聚酰亚胺具有较高的玻璃化转变温度(T_g,在544～562K之间),且与主链中染料发色团的含量无关.所有聚酰亚胺都表现出优良的高温稳定性,其5%热失重温度(T₅)比T_g高出100K以上,基本能满足电场极化对聚合物材料热稳定性的要求.另外,FPI(x)系列聚酰亚胺的紫外截止吸收波长小于500nm,即在大于500nm波长范围内基本透明.其面内折光指数n_TE随着染料发色团含量的增加而逐渐增加.     

一种以环戊并双噻吩作为π电子桥的新型发色团的合成和电光性质的表征

本文以4,4-二己基-4H-环戊并[2,1-b:3,4-b′]二噻吩为π电子桥,合成了一种新型非线性光学发色团,并通过紫外-可见吸收光谱、热重分析以及密度泛函理论计算等对其物理和化学性质系统地进行了表征。结果表明,4,4-二己基-4H-环戊并[2,1-b:3,4-b′]二噻吩作为π电子桥能有效地提高分子内的电荷转移速率和分子的一阶超极化率。同时,侧链二己基的空间位阻效应能很好地削弱分子间静电相互作用。最后,将发色团掺杂到主体聚合物聚碳酸酯中,测试得到发色团浓度为20%的极化聚合物薄膜的电光系数r33为85pm/V。     

可注射性骨组织工程支架材料不饱和聚磷酸酯的合成

以富马酸、1,2-丙二醇和三氯氧磷为起始原料,合成了主链重复结构单元中含不饱和双键的聚磷酸酯.FTIR及NMR研究表明.不饱和聚磷酸酯(UPPE)主链结构中含有富马酸二(1,2-丙二醇)酯(BPGF)的三种异构体.利用GPC研究了反应时间对聚合反应的影响,结果表明,延长反应时间有利于提高分子量,聚合物趋向于单分散性.反应18 h后,聚合物重均分子量达到5 956 g/mol,分散度为1.12.通过测定UPPE与N-乙烯基吡咯烷酮(NVP)的交联温度曲线,确定交联反应最高温度为41.14-82.30℃,固化时间在1.95-10.28 m in之间.     

Interpenetrating polymer networks with stable second order nonlinear optical properties

Interpenetrating polymer networks (IPNs) based on polyurethane and polyacrylate-containing 4-(4'-nitrophenylazo) aniline chromophore groups were synthesized and characterized by infrared spectra, gel content and differential scanning calorimetry. Thin, transparent films of the IPNs were prepared by spin-coating, followed by thermal curing and corona poling. The poled IPN film shows very good optical properties and exhibits only one glass transition temperature. The second-order nonlinear optical (NLO) properties of the poled film were studied by visible light absorbance measurement according to one-dimensional rigid oriented gas model. The second-order nonlinear optical polarizability can reach 10^-7 e.s.u. The poled IPN film of defined composition showed a good temporal stability of NLO properties at 120°C for more than 160 hr.     

Synthesis and characterization of NLO chromophores bearing poly(1,6-heptadiyne)s for electro-optic application

We utilized the metathesis reaction to synthesize a new type of multifunctional polymer that contains a conjugated backbone and a second-order NLO chromophore as a pendant group. The 1,6-heptadiyne derivatives bearing NLO chromophores were easily polymerized by using a metathesis catalyst to give corresponding polymers with large optical nonlinearities. Molecular structural characterizations for the resulting polymers were achieved by ¹H- and ¹³C-NMR, FTIR, and UV-visible spectroscopies. Soluble polymers were obtained up to 72 mol % of chromophore monomer portion in the copolymer. These amorphous polymers exhibited good film-forming abilities and thermal stability. The electro-optic coefficient, r₃₃, of the poled polymer films was in the range of 0.5–10.1 pm/V, and the nonresonant values of the third-order NLO coefficient, χ⁽³⁾ was found to be about 10⁻¹¹ esu. © 1996 John Wiley & Sons, Inc.     

Quadratic nonlinear optical and preliminary piezoelectric investigation of crosslinked samples obtained from a liquid chromophore

A push–pull chromophore has been synthesized, which is liquid at room temperature and can be crosslinked owing to the presence of two methacrylate moieties. Thin films of the chromophore have been prepared by spin coating, and they have been simultaneously crosslinked and poled under strong electric field. On the poled crosslinked films, the quadratic nonlinear optical (NLO) characterization was performed through nonresonant second harmonic generation measurements at 1368 nm as the fundamental wavelength, yielding a fairly good d₃₃ value of 46 pm/V, with retention of 80% of that value after 2 months at 85 °C. Following the theoretical issue that the quadratic NLO and piezoelectric tensors of a material have the same symmetry properties, and exploiting the easy processing of the chromophore in the liquid phase, we have prepared poled crosslinked samples of the chromophore suitable for piezoelectric tests that were performed using a commercial piezoceramic sample as the reference. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012     

In situ poling and orientation stability of chromophore-bearing ladderlike polysiloxanes

A new, specially designed nonlinear optical (NLO) polymer is composed of ladderlike polysilsesquioxane as a backbone and “side-on or end-on” fixed stilbene chromophores. In-situ poling was carried out simultaneously during film formation via solvent evaporation and crosslinking which was caused by sequential hydrolysis and condensation of remained Si-H groups on macromolecules. The dipolar orientation after poling is described by an order parameter Φ which was measured using an original linear optical technique–UV dichroism. Orientation order and its decay are influenced by chromophore loading, crosslinking degree and poling condition. Compared with corresponding single chain polymers, a poled thin film of ladderlike NLO polymers demonstrates more stable poling-induced orientation.     

新型非线性光学杂化材料结构与性能的研究

由硅烷染料ASD与钛酸四正丁酯在酸性条件下共水解、缩合得到杂化材料,利用透射电镜(TEM)和X射线能量色散谱仪(EDS)进行分析,结果表明,杂化溶胶粒子是由硅和钛的化合物组成的球形纳米粒子.由一维刚性取向气体模型计算杂化材料膜再极化后的二阶非线性光学系数χ⁽²⁾为1.43×10^-7esu.差示扫描量热法(DSC)测得杂化材料的玻璃化温度可达469K;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.用原子力显微镜(AFM)和X射线衍射(XRD)研究了材料在极化过程中的结晶行为和微观结构对生色团取向稳定性的影响,初次在这种极化后的膜中观察到了介观结构.     

Investigation of dipole alignments by swelling in poled thin films of a side-group polymer using second harmonic generation

This paper deals with relations between solvent diffusion and changes in second harmonic generation (SHG) in a side-group polymer with nonlinear optical (NLO) chromophores. The SHG signal of poled polymer thin films was measured as a function of time during the swelling process with methanol. The results indicated that the diffusion process was Fickian. The topographic results obtained by atomic force microscopy, together with the SHG data, also demonstrated the existence of the domain layer formed during poling that gave rise to the principal SHG intensity for this sample. Also, a noncentrosymmetric chromophore ordering was induced by swelling in the absence of a poling electric field. This time-varying SHG signal upon swelling was discussed in terms of dipolar and polar alignments of the side-group NLO chromophores. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 3108–3114, 1999     

聚酰亚胺多层膜的制备及其在非线性光学中的应用

报道了一种通过旋涂制备NLO聚合物多层膜的方法.紫外-可见吸收光谱及膜的厚度表征说明,在所得多层膜的结构中,聚合物单层膜的厚度可以较好地控制在100~200nm之间,所得含有5个双层的NLO多层膜(厚度1.6μm)具有良好的结构均一性,光学显微镜下没有观察到明显的结构缺陷.与单层具有较大厚度的NLO聚合物薄膜(如2~4μm)相比,所得聚合物多层膜可以允许掺杂更多的发色团而不发生相分离.     

Synthesis and nonlinear optical properties of methacrylate polymers based on 2‐[4‐(N‐methyl,N‐hydroxyethylamino)phenylazo]‐phenyl‐6‐nitrobenzoxazole chromophore

Methacrylate polymers containing different molar contents of nonlinear optical (NLO) active molecular segments based on 2‐[4‐(N‐methyl,N‐hydroxyethylamino)phenylazo]‐phenyl‐6‐nitrobenzoxazole chromophores were synthesized, and their phase behavior and second‐order NLO properties were investigated. Polymers containing 6–17 mol % chromophore segments allowed the preparation of amorphous and optically clear thin films. Some mesomorphic structuration was exhibited by a polymer with 33 mol % chromophoric units. However, this feature did not prevent the possibility of investigating the NLO properties. Nonlinear resonance‐enhanced d₃₃ coefficients were determined by second harmonic generation experiments on spin‐coated, corona‐poled thin films at λ = 1064 nm. Values ranging from 40 to 60 pm/V were measured with increasing chromophore molar contents. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 1841–1847, 2003