A NOVEL EOR POLYMER (Ⅰ)—STUDY ON GELATION OF RESORCINOL-FORMALDEHYDE SYSTEMS

Factors affecting the gelation of resorcinol-formaldehyde systems have been examined overvariable ranges applicable to oilfield use. Gelation of resorcinol-formaldehyde (RF) system wassensitive to pH,salinity and hardness. Generally,this gel system could be used in fresh water orlow salinity brine at pH higher than about 9. The application would require careful monitoring ofinjection fluids to avoid premature gelation or prolonged shut-in times,especially under conditionsof low salinity and high pH. Salinity and hardness compatibilities of the system were improved bysulfomethylation of resorcinol. Aqueous sulfomethylated resorcinol formaldehyde (SMRF)system could be used in brine with higher salinity and hardness and at a wider pH range of 5--10.

Synthesis of melamine-formaldehyde microcapsules containing oil-based fragrances via intermediate polyacrylate bridging layers

A general and versatile strategy to prepare melamine-formaldehyde(MF)microcapsules encapsulating oil-based fragrances by combining solvent evaporation and in situ polymerization was proposed in this work.The oil-based fragrance was pre-encapsulated by an inner polyacrylate membrane via solvent evaporation,followed by in situ polymerization of MF precondensates as an outer shell.The polyacrylate membrane is used as an intermediate bridging layer to stabilize the oil-based fragrance,and to provide driving forces for in situ polymerization of MF precondensates through electrostatic attractions between carboxyl groups and ammonium ions.It was demonstrated that MF microcapsules containing clove oil were prepared successfully.The amount and the composition of the intermediate polyacrylate bridging layer were critical.Smooth and sphere-shaped MF-clove oil microcapsules were prepared when the weight ratio of polyacrylate to clove oil was over 60 wt%and the concentration of acrylic acid(AA)increased to 10 wt%in polyacrylate.In addition,MF microcapsules containing sunflower oil and hexyl salicylate were prepared by using this method.The work suggests that this new approach can be potentially used to encapsulate various core materials,tuning the shell properties of microcapsules such as thickness,mechanical strength and release properties.

A NOVEL EOR POLYMER (Ⅱ)——INVESTIGATION ON IN-SITU GELATION OF SMRF SYSTEM IN BEREA CORE

In-situ gelation of aqueous sulfomethylated resorcinol formaldehyde (SMRF) system inBerea core has been investigated. Two sets of displacement experiments were conducted with thissystem (containing 5% NaCl, 0. 036% CaCl_2. 2H_2O). The brine permeabilities of the coreswere reduced significantly from about 600 to 0.1 md. The in-situ gelation in Berea core occurreda little bit earlier than gelation anticipated from bulk test in the experiments. The gel time waseasier to control at initial pH between 6 and 8. During injection of SMRF system, the apparentviscosity was less than 1 mPa·s at 41℃.

Effect of Multi-Hydroxyl Polymer-Treated MUF Resin on the Mechanical Properties of Particleboard Manufactured with Reed Straw

The poor bonding performance between aqueous adhesives represented by melamine-urea formaldehyde(MUF)resins and reed straw hinders their applications in the field of non-wood-based panels.Multi-hydroxyl polymers are highly reactive and are often used as crosslinkers.This study fabricated a resin with a strengthened crosslinked structure by combining a multi-hydroxyl polymer and MUF resin prepolymer.The reed particleboard was prepared by using this resin as an adhesive and reed stalk as the matrix.The results show that neighboring molecules combined to form C–O–C bonds that strengthened the cross-linked structure of the resin.In addition,the viscosity of the resin was increased,and a continuous adhesive layer on the surface of reed particles was formed,which slowed the penetration of reed particles.The adhesive layer significantly improved the mechanical properties of the reed particleboard.The maximum modulus of rupture(MOR),modulus of elasticity(MOE),and internal bonding strength(IB)of the reed particleboard were 33.53,4126,and 0.79 MPa,respectively.The IB of the board was 3.3 times higher than that of the reed particleboard prepared with a conventional MUF resin.Reed straw is a non-wood biomass material that has the advantage of sustainable development and may replace woodbased materials to produce particleboard.This resin-prepared reed particleboard is expected to be used in areas such as custom furniture and engineering materials.

双氰胺甲醛改性汉麻纤维吸附剂的制备及对阴离子染料的吸附

针对双氰胺甲醛(DDF)对染料废水脱色时pH适用范围狭窄、难分离回收等问题,采用3-氨丙基三乙氧基硅烷(APTES)偶联剂将DDF接枝到汉麻纤维(HF)上,制备一种适用于去除阴离子染料的广域pH高效吸附剂(HF-APT-DDF)。考察了不同因素对单一组分和混合组分下刚果红(CR)、酸性兰9(AO 9)和活性嫩黄K-6G(RBY K-6G)3种染料吸附性能的影响。结果表明:HF-APT-DDF在pH=4~10的范围内均具有良好的脱色效果;在温度为298 K、染料初始浓度为20 mg/L、pH为8、吸附时间为1.5 h、投加量为1.0和1.4 g/L时,HF-APT-DDF对单一组分和混合组分染料的脱色率均超过97%,对CR、AO 9和RBY K-6G的最大吸附量分别为116.62,80.16和103.86 mg/g;5次循环使用后,HF-APT-DDF脱色率仍在80%以上;无机盐离子对吸附性能的影响从大到小为PO_(4)^(3-)>CO_(3)^(2-)>SO_(4)^(2-)>NO_(3)^(-)>Cl^(-);HF-APT-DDF对染料的吸附是自发的放热过程,遵循准二级动力学模型和Langmuir等温吸附模型。

比较两种常见的前驱物合成的聚合物及碳基微球材料

聚合物/碳基微球材料以其独特的骨架结构、优异的物理化学性能及广阔的应用前景,成为当下纳米材料研究和开发的热点领域之一。近年来,人们发展了两种常见的前驱物——间苯二酚/甲醛和多巴胺,来相对容易地在实验室合成制备聚合物/碳基微球材料。对这两种前驱物的不同的组成、化学结构、聚合反应机理等进行了系统的比较。此外,围绕合成与应用,对该领域研究存在的机遇与挑战进行了合理的展望。

矿用高分子材料液体组分中游离甲醛测量不确定度评定

对煤矿用反应型高分子材料液体组分中游离甲醛测量进行不确定度评定,可为试验室游离甲醛含量测定结果质量控制及检测报告的合理性提供科学依据。按照现行标准AQ 1116—2020及GB 18583—2008对装修材料胶黏剂中有害物质限量的规定,采用乙酰丙酮分光光度法测定煤矿用反应型高分子材料液体组分中游离甲醛含量,并对测量结果的不确定度进行评定。矿用反应型高分子材料液体组分中游离甲醛含量在95%置信概率(k=2)下的测定结果为(0.0568±0.0019)g/kg。结果表明,影响测量不确定度的主要因素包括称量样品、样品吸光度测量重复性、标准曲线绘制以及移取和定容溶液过程等引入的相对标准不确定度,而标准曲线绘制、移取和定容溶液过程是引起测量不确定度的主要因素。为了提升试验室测量结果的准确性,关键在于规范玻璃仪器的使用以及准确进行精细化标准溶液吸光度测试。

双氰胺-甲醛聚合物阳离子印染废水脱色剂的合成及其应用

合成出一种以双氰胺、甲醛为原料的阳离子印染废水高效有机脱色剂,考察了双氰胺、甲醛、硫酸铝用量和反应温度、反应时间等合成条件对双氰胺-甲醛聚合物脱色性能的影响.结果表明,优化合成工艺条件为双氰胺:甲醛:硫酸铝=1:2.58:0.35(摩尔比)、80℃、反应3h.所制脱色剂对分散红167、BES蓝、分散蓝79三种典型染料废水的脱色率均达98%以上.脱色机理主要包括吸附电中和作用、压缩双电层、吸附架桥、网捕作用.将脱色剂应用于江苏省常州市马杭污水厂混合印染废水的处理,在pH8、投加量17.5mL/L的条件下,脱色率可达96%以上,出水色度从360倍降为10倍,达到GB8978-1996一级A排放要求.

双氰胺-甲醛聚合物-聚合氯化铝复合絮凝剂的合成及应用

以双氰胺、甲醛、氯化铝为主要原料,加入添加剂合成了双氰胺-甲醛聚合物(DF)-聚合氯化铝(PAC)复合絮凝剂。采用模拟印染废水考察了各种因素对DF-PAC复合絮凝剂混凝脱色性能的影响。实验结果表明,在双氰胺、甲醛、氯化铝、添加剂加入量分别为29.1,57.8,4.8,12.5g,反应温度(70±1)℃、反应时间2.5h的条件下制得的DF-PAC复合絮凝剂的絮凝脱色性能良好,COD去除率不小于90%,色度去除率不小于99%。与PAC和DF絮凝剂相比,DF-PAC复合絮凝剂对实际印染废水的絮凝脱色效果更好。

漆酚醛缩聚物/丙烯酸树脂IPN涂料的制备及性能

用多羟基丙烯酸树脂(MPA)对漆酚缩甲醛 (UFP)涂料进行改性,制备了兼具耐热和抗紫外性能的UFP/MPA互穿聚合物网络涂料,用IR、TG -DSC、DMTA等进行了结构表征和性能测试。结果表明,当m(UFP)∶m(MPA) =5∶2时,UFP与MPA相互交联、缠结;其涂膜既耐热又抗有机溶剂,光照 7d后仍兼具有UFP和聚丙烯酸酯的优良性能:硬度为 6H、柔韧性为 1mm、附着力为 1级。

新型淀粉接枝双氰胺甲醛缩聚物絮凝剂的制备及反应机理研究

阳离子型接枝淀粉絮凝剂是一种高效环保、安全稳定、经济适用的絮凝剂,但其制备工艺较为复杂,同时,用于接枝的阳离子型乙烯基单体种类较少。为此,设计并制备了一种淀粉基接枝双氰胺甲醛缩聚物絮凝剂,并通过红外分析确定了其分子结构和特征基团。实验结果表明,利用这种絮凝剂(用量为7.5%)处理2 g/L的尤丽素红E-B染料模拟废水,脱色率达到98.3%;在相同用量下,该絮凝剂可使制浆中段废水的COD从200 mg/L降至34 mg/L,COD去除率达到83.0%。

一种复合脱色剂在印染废水中的应用研究

以甲醛、双氰胺、醋酸钠、氯化铵、氯化铝等为原料制备了一种印染废水脱色絮凝剂T-1。采用福州某纺织印染有限公司的印染废水为处理对象,以脱色率为主要考核指标,讨论了T-1的投加量、pH值、废水温度等对絮凝效果的影响。实验结果表明,双氰胺-甲醛缩聚物对印染废水具有优良的脱色絮凝效果,当投加量为100mg/L,废水温度为30℃,pH=8时,处理效果最佳,色度去除率达70%,COD去除率为78.3%。而且其絮凝性能明显优于聚合氯化铝(PAC)、聚合硫酸铝(PAS)絮凝剂。

采用双氰胺甲醛缩聚物混凝去除水中酸性红B染料的研究

以双氰胺和甲醛为原料制备了聚合双氰胺甲醛，并对其进行红外光谱表征。采用聚合双氰胺甲醛与硫代硫酸钠共同作用对酸性红B染料溶液进行混凝脱色实验。对比了单独使用聚合双氰胺甲醛，以及聚合双氰胺甲醛与硫代硫酸钠共同作用的脱色效果。探讨了硫代硫酸钠和聚合双氰胺甲醛的用量以及pH值对脱色率的影响。结果表明，投加硫代硫酸钠可以明显地提高聚合双氰胺甲醛的脱色率，增大絮凝范围，使絮凝剂对pH值的变化有很强的适应性，pH值为7～12的范围内，脱色率均能维持在96％以上。此外，还对混凝脱色的机理进行了研究。

硫酸铝催化合成双氰胺-甲醛絮凝剂的研究

以双氰胺、甲醛为主要原料,以硫酸铝为催化剂并引入添加剂合成了双氰胺-甲醛树脂高效脱色阳离子有机絮凝剂-双氰胺-甲醛树脂。探讨了甲醛用量、催化剂用量、反应温度、反应时间、添加剂用量对双氰胺-甲醛树脂产品混凝脱色性能的影响,并对染料废水进行了混凝脱色试验。该絮凝剂较其他絮凝产品在污水处理、降低色度、悬浮物和COD去除等方面效果显著。

双氰胺改性胶原蛋白复鞣填充剂的研究

以双氰胺、甲醛、硫代硫酸钠和胶原蛋白为主要原料,合成了一种新型的低游离甲醛含量的双氰胺改性胶原蛋白复鞣填充剂(DPR)。对所得产品进行了红外谱图表征,结果显示产品双氰胺和胶原蛋白发生了化学反应;并将所得的产品应用于皮革复鞣填充,对复鞣后成革的各项性能进行测定,结果显示复鞣后成革丰满柔软,粒面紧实,复鞣后革平均增厚率为11.51%,染料上染率为98.7%,抗张强度为25.31N·mm-2,柔软度为6.53,透水汽性为7.0mg·cm-2·h-1,其综合性能优于R6产品。

二羟甲基脲及其缩聚物的合成与表征

以尿素和甲醛为原料,在碱性水溶液中合成了二羟甲基脲,利用FTIR,1HNMR和元素分析对其结构进行了表征.同时以二羟甲基脲为原料,通过熔融缩聚制备了脲醛缩聚物,通过FTIR,1H NMR,1 3 C NMR和15N NMR对其结构进行了表征.实验结果表明:经二羟甲基脲熔融缩聚制备的长效脲醛缓释化肥,其可利用指数(AI)为98.6%,证明该法是合成长效脲醛肥料的有效途径.

漆酚缩甲醛钼高聚物的合成与表征

由漆酚缩甲醛聚合物 ( PUF)与四氯氧化钼合成了漆酚缩甲醛钼高聚物 ( PUFM) ,并对其进行了表征 .实验结果表明 :四氯氧化钼用量对 PU FM的吸光度、涂膜物理性能以及贮存期都有直接的影响 ,PUFM的分子量及其分子量分布宽度均较漆酚缩甲醛聚合物的大 .红外光谱、紫外光谱和荧光光谱等测试结果都证明漆酚缩甲醛聚合物与四氯氧化钼发生了配位和交联反应 .PUFM具有很高的热稳定性 ,PUFM膜具有良好的物理性能和耐化学腐蚀性能 .若将 PUFM制成漆酚缩甲醛钼黑推光漆 ,可克服原黑推光漆粘度大。

阳离子型DF/PAC复合絮凝剂处理活性印染废水

针对印染厂生产废水,以COD和色度为指标,用混凝试验方法,研究了碱化度为1.6的聚合氯化铝(PAC)和黏度为560mPa·s的双氰胺-甲醛缩聚物(DF)以及阳离子型DF/PAC复合絮凝剂对活性印染废水的处理效果。考察了絮凝剂的沉降效果和絮凝剂的投加量及投加方式对絮凝脱色效果的影响,探讨了废水pH值对阳离子型DF/PAC复合絮凝剂絮凝脱色性能的影响。结果表明,DF/PAC可有效地去除印染废水中的COD和色度,当pH为6～9、沉降时间为35min、投药量为1.0mg/L时,去除效果最佳,COD去除率≥90%,脱色率≥99%;相对于PAC和DF,DF/PAC产生的絮体大而密实,沉降速度快、产生污泥量少,药剂用量少,出水水质为:COD<80mg/L,色度<30倍。

印染废水高效脱色絮凝剂的合成及其脱色性能研究

合成了改性甲醛-双氰胺系列脱色絮凝剂T5,该絮凝剂合成条件简单,成本较同系列的产品低,每吨为3400元左右。T5用于处理印染废水效果好,脱色率和CODCr去除率均较高,污泥体积小。T5与Al2(SO4)3复配使用效果更佳,脱色率达96.8%,CODCr去除率最高可达91.5%;出水CODCr和色度达国家一级排放标准。

自修复聚合物材料用微胶囊

Microcapsules with dicyclopentadiene(DCPD) as core material and urea formaldehyde resin as wall material used for making self-healing polymer material were prepared with the in-situ polymerization method.The effect of microcapsules on the fracture toughness of epoxy resin was studied.The addition of microcapsules into epoxy resin results in the decrease of fracture toughness.When microcapsule content was kept constant,as the microcapsule size increased the fracture toughness of the epoxy resin decreased linearly and the percentage of decrease compared to the neat epoxy without microcapsules increased linearly.Moreover, the fracture toughness of the material decreases linearly with the increase of microcapsule content.