PREPARATION AND CHARACTERIZATION OF AFFINITY POLYMER BASIC MICROSPHERES BY SOAP-FREE EMULSION POLYMERIZATION

Poly(styrene-co-glycidyl methacrylate) latex microspheres with uniform size and high-density epoxy groups on the surface were prepared by soap-free emulsion polymerization with batch wise operation mode in the presence of 2.2′- azobis(2-methylpropionamidine) dihydrochloride as an initiator.The kinetics of soap-free emulsion polymerization and the effects of polymerization factors were examined.In addition,the optimum polymerization conditions of poly(styrene-co- glycidyl methacrylate) latex microspheres for...

SYNTHESIS OF SOAP-FREE ACRYLIC HYDROSOLS

Poly(methyl methacrylate/ethyl acrylate/acrylic acid) hydrosols were prepared by employing soap-free polymerization, and (acrylic acid/butyl acrylate) oligomer was used as the polymeric surfactant. The effect of reaction condition on the morphology and particle size of the hydrosols was investigated. The minimum amount of acrylic acid in the hydrosols is 2%. The maximum weight average molecular weight (M-w) of polymer that assures soap-free emulsion conversion into hydrosol is about 1.2 x 10(5)-1.3 x 10(5). The particle transforming process was investigated, and an obvious change of particle diameter and morphology was observed.

Influences of Electrolytes on the Soap-free Emulsion Copolymerization of St-MMA-AA

Monodisperse functional polymer microspheres with different particle size and with clean surface were prepared by batch soap-free emulsion polymerization of styrene, methyl methacrylate and acrylic acid in the presence of salts, and the influences of type and amount of electrolytes on polymerization process and particle morphology were investigated. Results showed that there was a critical concentration for different electrolyte to make polymerization process and the resultant emulsion stable, and the particle size increased with the increase of electrolyte concentration. The effect of metal ions was Ca^2＋〉〉K^＋〉Na^＋〉Li^＋, and the effect of haloids was Br〉Cl〉F. Keywords： Electrolyte, soap-free emulsion polymerization, polystyrene, latex particle morphology.

Preparation of Self-crosslinked Fluorocarbon Polymer Emulsion with Core-shell Structure by the Method of Soap-free Emulsion Polymerization

Using methyl methacrylate （MMA）, butyl acrylate（BA） and hexafluorobutyl acrylate（HFBA） as main raw materials, we prepared self-crosslinked fluorocarbon polymer emulsion with core-shell structure via soap-free emulsion polymerization when the conception of particle design and polymer morphology was adopted. Moreover, the influence of mole ratio of BA to MAA, pH value on the oligomer was studied. And the effects of the added amount of oligomer, self-crosslinked monomer and HFBA, mass ratio of BA to MMA, reaction temperature and the initiator on the polymerization technology and the performance of the product, were investigated and optimized. The structure and performance of the fluorocarbon polymer emulsion were characterized and tested with FTIR, TEM, MFT and contact angle and water absorption of the latex film. The experimental results show that the optimal conditions for preparing fluorocarbon polymer emulsion are as follows： for preparing the oligomer, tool ratio of BA to MAA is equal to 1.0 ： 1.60, and pH value is controlled within the range of 8.0 and 9.0; for preparing fluorocarbon polymer emulsion, the added amount of oligmer[P（BA/MANa）] is 6%; mass ratio of BA to MMA is 40 ＂ 60; the added amount of self-crosslinked monomer is 2%, the added amount of HFBA is 15 %; reaction temperature is 80 ℃; the mixture of potassium persulfate and sodium bisulfite is used as the initiator. The film-forming stability of the fluorocarbon polymer emul- sion and the performance of the latex film, which is prepared with the soap-free emulsion polymerization, are better than that prepared with the conventional emulsion polymerization.

Synthesis and Characterization of Poly (Methyl Methacrylate)/Polyethylenimine Grafting Core-Shell Nanoparticles for CO2 Adsorption Using Soap-Free Emulsion Copolymerization

Unlike previous emulsion polymerization, we used grafting reactions in soap-free emulsion systems. In this study, we synthesized grafted PMMA/PEI core-shell nanoparticles by varying the MMA/PEI content and molecular weight of PEI (Mn = 600, 8000, and 10,000). The size and morphology of the core-shell nanoparticles were characterized by a particle size analyzer and scanning electron microscopy. The nanoparticles were 178 - 408 nm in diameter and swelled in water or methanol by 30 - 75 nm. The size of the nanoparticles increased with MMA contents, whereas the size distribution progressively became homogeneous with increasing molecular weight of PEI. Lastly, we measured CO2 adsorption capacity of the grafted PMMA/PEI core-shell nanoparticles, and we found the capacity to be limited at a level of 0.69 mg, which occurred for nanoparticles prepared from emulsions at a pH value of 11.

INFLUENCES OF ACID POST-TREATMENT ON THE MORPHOLOGY OF SOAP-FREE P(MMA-EA-MAA)PARTICLES PREPARED BY SEEDED EMULSION POLYMERIZATION

Soap-free poly（methyl methacrylate-ethyl acrylate-methacrylic acid） latex particles with narrow size distribution were synthesized by seeded emulsion polymerization, and the porous particles were created by a stepwise alkali/acid treatment method. Effects of acid treatment conditions on the particle morphology were investigated. Results show that one to three pores were formed inside most of particles after post-treatment. At pH 7.0, when the treatment temperature was lower than 70℃, the size of particles and the volume of pores remained almost unchanged, and these two values increased significantly when the temperature was higher than 70℃. Both the particle size and the pore volume decreased with the increase of initial pH value and treatment time in the acid treatment. As the pH was below 4.0 and the treatment time was longer than 180 min, the particles shrunk in size.

A New Kind of Void Soap-free P(MMA-EA-MAA) Latex Particles

Soap-free P(MMA-EA-MAA) particles with narrow size distribution were synthesized by seeded emulsion polymerization of methyl methacrylate (MMA), ethyl acrylate (EA) and methacrylic acid (MAA), and large voids inside the particles were generated by alkali posttreatment in the presence of 2-butanone. Results indicated that the size of void and the particle volume were related with the amount of 2-butanone. The generation mechanism of voids was proposed.

Synthesis of submicron-sized peanut-shaped poly(methyl methacrylate)/polystyrene particles by seeded soap-free emulsion polymerization

Submicron-sized peanut-shaped poly（methyl methacrylate）/polystyrene （PMMA/PS） particles were successfully synthesized by seeded soap-free emulsion polymerization of styrene on the spherical crosslinked PMMA seed particles. The obtained peanut- shaped particles showed a novel internal morphology： PS phase formed one domain which linked to the other domain having PMMA core encased by PS shell.

DESIGN AND CONTROL OF SOAP-FREE HYDROPHILIC-HYDROPHOBIC CORE-SHELL LATEX PARTICLES WITH HIGH CARBOXYL CONTENT IN THE CORE OF THE PARTICLES

Soap-flee hydrophilic-hydrophobic core-shell latex particles with high carboxyl content in the core of the particles were synthesized via the seeded emulsion polymerization using methyl methacrylate （MMA）, butyl acrylate （BA）, methacrylic acid （MAA）, styrene （St） and ethylene glycol dimethacrylate （EGDMA） as monomers, and the influences of MMA content used in the core preparation on polymerization, particle size and morphology were investigated by transmission electron microscopy, dynamic light scattering and conductometric titration. The results showed that the seeded emulsion polymerization could be carried out smoothly using ＂starved monomer feeding process＂ when MAA content in the core preparation was equal to or less than 24 wt%, and the encapsulating efficiency of the hydrophilic P（MMA-BA-MAA- EGDMA） core with the hydrophobic PSt shell decreased with the increase in MAA content. When an interlayer of P（MMA- MAA-St） with moderate polarity was inserted between the P（MMA-BA-MAA-EGDMA） core and the PSt shell, well designed soap-free hydrophilic-hydrophobic core-shell latex particles with 24 wt% MAA content in the core preparation were obtained.

PREPARATION OF MICRON-SIZED NONSPHERICAL POLYSTYRENE/POLY(STYRENE-co-ETHYLENEGLYCOL DIMETHACRYLATE) PARTICLES BY SEEDED SOAP-FREE EMULSION POLYMERIZATION

Micron-sized nonspherical polymer particles having different morphologies were synthesized by seeded soap-free emulsion polymerization of styrene （St） and ethyleneglycol dimethacrylate （EGDMA, used as a crosslinker） on spherical, linear polystyrene （PS） seed particles. The morphology of the resulting PS/poly（St-co-EGDMA） particles was dependent on the crosslinker concentration and polymerization temperature.

微波辐射无皂乳液聚合法制备单分散交联PMMA微球及其性能研究

采用无皂乳液聚合法,以二乙烯苯为交联剂,氯化钾为电解质,过硫酸钾为引发剂,在微波辐射条件下制备了聚甲基丙烯酸甲酯(PMMA)微球。研究了过硫酸钾和氯化钾的物质的量浓度对PMMA微球的平均粒径和多分散性指数的影响,分析了微波功率、搅拌速度与PMMA微球形貌和粒径的关系。检测了不同pH值时PMMA乳液的电动(Zeta)电位,表明PMMA表面产生负电荷,使PMMA微球呈现稳定的分散状态。制备的PMMA呈现类球形,粒径为100~400 nm,在过硫酸钾物质的量浓度为5.69×10^(-3)mol/L及氯化钾物质的量浓度为1.03×10^(-2)mol/L时,微球的多分散性指数<0.1。原子力显微镜检测了最优工艺条件下,PMMA微球的力—位移曲线并分析了其弹性力学性能。

石蜡Pickering乳液及其微胶囊相变非织造材料的制备与性能

Pickering乳液固含量和储存稳定性等性能显著优于传统乳液,但是,其乳化剂品种仍然稀缺,以苯乙烯(St)、甲基丙烯酰氧乙基三甲基氯化铵(DMC)为主要单体,二乙烯基苯(DVB)为交联剂,乙醇为助溶剂,用无皂乳液聚合法制备了阳离子型共聚物颗粒(P(St-co-DMC)),并将其作为乳化剂制备了石蜡Pickering乳液;并将石蜡乳液浸渍粘胶水刺非织造布制备石蜡微胶囊相变材料(Vis-PCM)。借助红外光谱仪、扫描电子显微镜、热重/差热联用仪、差示扫描量热仪和接触角测量仪等对共聚物及相变材料微观结构与性能进行表征与测试。实验结果表明:随着DMC用量、引发剂用量和乙醇含量的增加,单体转化率先增大后减小,P(St-co-DMC)粒径和分散指数先减小后增大,其Zeta电位则先快速增大而后趋于恒定,而亲水性持续增强;所得石蜡Pickering乳液的油水体积比高达3∶1,储存稳定性超过3个月;Vis-PCM的相变潜热高达139.3 J/g,经过20次冷热循环处理后,Vis-PCM中的石蜡泄漏率仅0.6%。本文制备的Vis-PCM具有良好的储热与放热性能,在相变储能领域具有广阔的应用前景。

IBVE/AANa/VAc无皂乳液的合成与性能

本文以异丁基乙烯基醚、丙烯酸钠和醋酸乙烯酯为反应单体合成无皂乳液。研究了AANa的用量对乳液稳定性的影响,考察了VAc/IBVE的比例与聚合物性能的关系,同时分析了乳胶粒的形貌。结果表明,亲水性单体AANa对乳液的稳定性、粒径大小影响较大。调整反应单体VAc/IBVE的比例可以得到不同分子量、不同玻璃化转变温度的聚合物,该无皂乳液具有明显的核壳结构。

聚丙烯酸酯无皂乳液的构建及对水性油墨性能的影响

以丙烯酸(AA)、丙烯酸丁酯(BA)、甲基丙烯酸甲酯(MMA)、丙烯酸羟丙酯(HPA)、2-甲基丙烯酸羟乙酯(HEMA)、乙烯基三异丙氧基硅烷(A-173)为单体,过氧化苯甲酰(BPO)、过氧化苯甲酸叔丁酯(TBPB)为引发剂,合成了丙烯酸酯大分子乳化剂,再通过无皂乳液聚合法合成了聚丙烯酸酯无皂乳液,将其与颜料等混合制备了水性油墨。采用FTIR、DSC、TEM、SEM对聚合物的结构及性能进行了表征,考察了不同BPO用量对丙烯酸酯大分子乳化剂的影响,不同AA添加量对乳液及水性油墨的影响。结果表明:当BPO用量为单体总质量的4.18%时,丙烯酸酯大分子乳化剂具有最低表面张力40.43mN/m;当AA添加量为单体总质量的1.00%时,聚丙烯酸酯无皂乳液具有合格的储存稳定性,乳胶膜拉伸强度可达5.00 MPa,断裂伸长率为200%,玻璃化转变温度为18.5℃,所制备的水性油墨黏度为23.79mPa·s,附着牢度90.75%,耐摩擦性4.5级。

高取代度阳离子淀粉基苯丙乳液的合成和应用研究

以苯乙烯(St)、丙烯酸正丁酯(BA)、丙烯酸叔丁酯(tBA)为单体,H2O2-FeSO4为引发体系,高取代度阳离子淀粉(HCS)为乳化剂,开展了苯丙表面施胶剂的无皂乳液聚合。探讨了HCS的用量、分子量(以特性黏度表示)、取代度对乳液聚合的影响,使用多种方法评价了乳液的理化性能与应用性能。所制备得的高取代度阳离子淀粉基苯丙乳液胶粒平均粒径小(126.2 nm)、正电性强(Zeta电位为25.8 mV)、贮存稳定性优良;将其应用在瓦楞原纸上,施胶纸张的Cobb值为21.6 g/m^(2),水滴接触角达121.6°,与低取代度阳离子淀粉基苯丙乳液相比,其应用效果具有明显优势。研究对其能赋予纸张更佳施胶效果的原因也提出了机理性的解释。

生态酶处理及新型活性染料染色短流程与免皂洗后处理工艺生产实践

前处理、染色到后处理都需经过染料、助剂等大量化学处理过程,各工序能源、热能和水的消耗量都很大,废水的电导率、COD高,污水处理难度大。通过大量生产实践,总结分析了公司自主开发的生态酶前处理工艺、新型活性染料染色短流程工艺及免皂洗后处理工艺,该前处理、染色、后处理工艺具备低温柔和、短流程、免皂洗等优点,大幅度降低了电导率、COD、污染和排放。

涤/棉织物分散/活性染料一浴染色的免还原净洗

为解决涤/棉分散/活性染料一浴染色织物普遍存在的牢度差问题,采用免还原净洗剂ST232,进行一次常规皂洗工艺,即可获得与传统两浴法染色工艺相当的净洗效果及色牢度。试验结果表明,较佳的皂洗工艺参数为ST232质量浓度4 g/L,氢氧化钠质量浓度1.5 g/L,温度100℃,洗涤时间5 min。该净洗剂对分散染料和活性染料均具有良好的洗涤能力,适用于分散和活性染料对涤/棉织物的一浴染色工艺。

涤棉织物染色免还原清洗短流程工艺开发

针对传统涤棉织物染色工艺流程长、耗时久、助剂用量大、耗水量大等问题,使用涤棉织物染色后一浴皂洗剂,开发染涤后免还原清洗直接染棉皂洗新工艺。与传统工艺相比,新工艺染涤后无须做还原清洗,直接染棉进行一浴皂洗,染色能耗降低,染后织物清洗用水减少,生产效率提升;工艺时间缩减28.00%以上,吨布耗水、耗电、耗汽分别节约24.50%、26.61%、6.99%,吨布助剂节约成本318.02元。使用新工艺进行涤棉织物染色,对织物色牢度、物性指标测试,统计能耗及助剂成本方面有明显优势,物性指标、各色牢度测试结果较传统工艺提升,助剂和能耗成本降低,符合现代化印染行业节能降耗、绿色发展趋势。