Cured melamine systems as thick fire-retardant layers deposited by combination of plasma technology and dip-coating

Melamine and melamine resins are widely used as fire-retardants for polymer building materials. Cured melamine systems are used in heat-sensitive items, such as furniture and window frames and sills. In this work, differently cured methylated poly(melamine-co-formaldehyde) (cmPMF) resins were used as fire-retardant coverage for poly(styrene) (PS) and poly(ethylene) (PE) building materials. Such polymer layers should have several tenths of micrometers thickness to produce sufficient fire retardancy. These thick layers were produced by dip-coating. To promote sufficient adhesion of such thick coating to the polyolefin substrates, also in the case of high temperatures occurring at fire exposure, the polymer substrates were firstly coated with a few hundred nanometer thick adhesion-promoting plasma polymer layer. Such thin plasma polymer layers were deposited by low-pressure plasma polymerization of allyl alcohol (ppAAl). It was assumed that the hydroxyl groups of ppAAl interact with the melamine resin; therefore, ppAAl was well suited as adhesion promoter for thick melamine resin coatings. Chemical structure and composition of polymer films were investigated using infrared-attenuated total reflectance and X-ray photoelectron spectroscopy (XPS). Peel strengths of coatings were measured. After peeling, the peeled polymer surfaces were also investigated using optical microscopy and XPS the layers for identification of the locus of peel front propagation. Thermal properties were analyzed using TGA (thermo-gravimetric analyses). Finally, the fire-retardant properties of such thick coated polymers were evaluated by exposure to flames.     

膨胀型防火涂料防火体系的研究

以聚磷酸铵(APP)/三聚氰胺(MEL)/双季戊四醇(DPER)为防火体系,自交联硅丙乳液为基质树脂的膨胀型防火涂料为研究对象,研究双季戊四醇对防火涂料耐水性和炭化层结构的影响,并采用正交试验对防火体系的配比进行优化.     

超薄膨胀型钢结构防火涂料的研制

以磷酸二氢铵、季戊四醇、三聚氰胺及丙烯酸树脂为原料研制了一种超薄膨胀型丙烯酸树脂钢结构防火涂料。并依据国家标准测定了不同配方防火涂料的理化性能和防火性能,分析了防火涂料的作用过程,并提供了相应的检测标准和测试结果,给出了性能优异的配方。阻燃体系(磷酸二氢铵、季戊四醇、三聚氰胺)的分解温度对防火涂料的性能有明显的影响;该配方使用原料简单、来源丰富、成本低、防火性能好。     

Adhesion promotion of thick fire-retardant melamine polymer dip-coatings at polyolefin surfaces by using plasma polymers

Melamine and melamine resins are widely used as fire retardants for polymer materials used in pharmaceutical, plastic, textile, rubber, and construction industry. Melamine-based flame retardants act by blowing off intumescent layers, char formation, and emission of quenching ammonia gas and diluent molecular nitrogen. Special advantages are: low cost, low smoke density and toxicity, low corrosive activity, safe handling, and environmental friendliness. Methylated poly(melamine-co-formaldehyde) (mPMF) was used as thick (≥40?μm) fire-retardant coating for plasma pretreated polymers. A combined low-pressure plasma pretreatment consisting of oxygen plasma exposure followed by deposition of thin poly(allylamine) (ppAAm) and poly(allyl alcohol) (ppAAl) plasma polymers as adhesion promoters have improved the adhesion of thick mPMF coatings strongly. Chemical structure and composition of deposited polymer films were characterized by infrared-attenuated total reflectance and X-ray photoelectron spectroscopy (XPS). After peeling, the peeled layer surfaces were also investigated for identification of the locus of failure and their topography using optical microscopy and XPS. Often the adhesion promotion was so efficient that the peeling of coating was not possible. Thermal properties of plasma polymers and dip-coating films were analyzed by thermogravimetric analysis. Significant improvement of fire-retardant properties of coated polymers was confirmed by flame tests.     

蜜胺-环氧树脂双层包覆聚磷酸铵及其阻燃PP的研究

针对聚磷酸铵(APP)耐水性不足、与聚丙烯(PP)等高分子材料相容性差等问题，采用甲醛-三聚氰胺(蜜胺树脂)和环氧树脂双层包覆了APP(EM-APP)，采用红外、扫描电镜、热重分析、溶解度测试等方式表征了包覆效果；采用水平垂直燃烧、氧指数仪和锥形量热仪、热重-红外联用等设备考察了包覆APP用于阻燃PP的效果，探讨了阻燃机理。结果表明：包覆操作不但有效提高了APP的耐水性，且将具有成炭功能的包覆层引入到APP表面；EM-APP相较APP，800℃时残炭量提高14.2%，在聚丙烯中加入同样质量份时，前者具有更高的阻燃效率，热释放速率、总热释放量、烟释放速率和总烟释放量都明显降低；包覆改善了APP与PP的相容性；燃烧过程中包覆层起到了协同成炭的作用。     

一种超薄膨胀型钢结构防火涂料的研制

以磷酸二氢铵、季戊四醇、三聚氰胺及丙烯酸树脂为原料研制了一种超薄膨胀型丙烯酸树脂钢结构防火涂料。并依据国家标准测定了不同配方防火涂料的理化性能和防火性能,分析了防火涂料的作用过程,给出了性能优异的配方设计。     

膨胀型阻燃剂磷酸-季戊四醇-三聚氰酰胺聚合物的合成及其在聚丙烯中的应用

研究了磷酸 -季戊四醇 -三聚氰酰胺聚合物的合成条件及膨胀效果 ,测定了阻燃聚丙烯的氧指数、水平燃烧性能 ,实验结果说明膨胀型阻燃剂的膨胀效果与组分有关 ,聚丙烯的阻燃效果随阻燃剂的膨胀效果增强 ,磷含量增大而显著改善。     

Study on flame retardance of co‐microencapsulated ammonium polyphosphate and dipentaerythritol in polypropylene

Co‐microencapsulated ammonium polyphosphate and dipentaerythritol [M(A&D)] was prepared using a melamine‐formaldehyde (MF) resin by in situ polymerization method, and characterized by XPS. The co‐microencapsulation of ammonium polyphosphate and dipentaerythritol (DPER) leads to a great improvement in water solubility of the additives. The flame retardant effect of M(A&D) in polypropylene (PP) is evaluated using limiting oxygen index (LOI) and UL 94 test, and the water resistance of the PP/M(A&D) composites is also studied. The flame retardant properties and water resistance of the PP/M(A&D) composites are much better than the ones of the PP/APP/DPER composites. Moreover, the thermal stability of the PP/M(A&D) composites is improved compared with the PP/APP/DPER composites. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers     

THE EFFECT OF COMPOSITION ON SURFACE PROPERTIES OF POLYESTER–MELAMINE THERMOSET COATINGS

Surface properties of polyester-melamine thermoset coatings have been investigated using XPS, thermal analysis methods, surface energy measurement, and small particle adhesion using a dedicated force rig. Bulk glass transition temperatures and surface energies changed little over a wide composition range (5–50?wt% melamine). At low melamine content (<20?wt%), particle adhesion behaviour was similar to that of pressure-sensitive adhesives; however, at high melamine contents particle adhesion was uniformly negligible. XPS and thermal analysis showed that at high melamine concentrations the surface melamine content was higher than expected, suggesting the formation of a hard, highly crosslinked, self-condensed, melamine-rich surface layer. This was not observed at lower melamine concentrations. The presence of this glassy melamine-rich surface layer is believed to be responsible for the low particle adhesion at high melamine concentrations.     

Plasma etching and plasma polymerization coating of carbon fibers. Part 2. Characterization of plasma polymer coated carbon fibers

Unsized AS-4 carbon fibers were subjected to RF plasma etching and/or plasma polymerization coating in order to enhance their adhesion to vinyl ester resin. Ar, N₂ and O₂ were utilized for plasma etching, and acetylene, butadiene and acrylonitrile were used for plasma polymerization coating. Etching and coating conditions were optimized in terms of plasma power, treatment time, and gas (or monomer) pressure by measuring the interfacial adhesion strength. Interfacial adhesion was evaluated using micro-droplet specimens prepared with vinyl ester resin and plasma etched and/or plasma polymer coated carbon fibers. Surface modified fibers were characterized by SEM, XPS, FT-IR, α-Step, dynamic contact angle analyzer (DCA) and tensile strength measurements. Interfacial adhesion between plasma etched and/or plasma polymer coated carbon fibers and vinyl ester resin was reported previously (Part 1), and characterization results are discussed is this paper (Part 2). Gas plasma etching resulted in preferential etching of the fiber surface along the draw direction and decreased the tensile strength, while plasma polymer coatings altered neither the surface topography of fibers nor the tensile strength. Water contact angle decreased with plasma etching, as well as with acrylonitrile and acetylene plasma polymer coatings, but did not change with butadiene plasma polymer coating. FT-IR and XPS analyses revealed the presence of functional groups in plasma polymer coatings.     

仿瓷阻燃脲醛涂料的研制

以改性的脲醛权脂为基料，磷酸和淀粉为阻燃剂制成膨胀型透明防火涂料，本文介绍了该涂料的配方和生产方法，讨论了改性的脲醛树脂结构，防火剂的组成及作用机理，列举了涂料的防火性能和理化性能的测试结果。     

阻燃型硝基清漆的研制

采用复合阻燃剂,以硝酸纤维素作为基料,同时加入氨基树脂和多种助剂,得到一种阻燃效果好的硝基清漆,研究了阻燃剂的种类及添加量、涂层厚度、涂刷次数等因素对阻燃效果和涂料理化性能的影响。实验结果表明:采用复合阻燃剂、阻燃剂的添加量为7%~10%,多次刷涂时,阻燃清漆有较好的综合性能。分析了阻燃剂的作用机理。     

改性丙烯酸树脂钢结构防火涂料制备研究

研究了以丙烯酸树脂为基料、三聚氰胺聚磷酸盐为脱水催化剂、季戊四醇为成炭剂、三聚氰胺为发泡剂,可膨胀石墨和Mg(OH)2纳米颗粒为复合阻燃剂的超薄型钢结构防火涂料.结果表明:可膨胀石墨与Mg(OH)2纳米颗粒具有协同作用,同时添加5%可膨胀石墨与1.5%Mg(OH)2,δ为1.80 mm时,涂料的t耐火达106 min.防火涂料的理化性能符合技术指标GB14907-2002的要求.     

固化剂对钢结构用超薄膨胀型水性环氧防火涂料性能的影响

以环氧乳液为基料,聚磷酸铵、三聚氰胺、季戊四醇(APP/MEL/PER)为防火助剂研制了超薄膨胀型钢结构防火涂料。通过调整环氧乳液/固化剂比例,研究了固化剂用量对涂料防火、防腐性能的影响。通过交联度测试进一步讨论了环氧乳液与固化剂比例对涂料性能的影响。结果表明:固化剂占环氧乳液含量20%时,涂层的防火性能和防腐性能均较好。     

氧化石墨烯提高钢结构水性膨胀防火涂料的防火性能研究

以水性丙烯酸树脂为基体,聚磷酸胺、季戊四醇和三聚氰胺为膨胀阻燃体系,加入少量氧化石墨烯制备水性膨胀防火涂料。采用小板燃烧法研究了氧化石墨烯用量对膨胀型防火涂料的阻燃性能的影响。结果表明:加入极少量氧化石墨烯(<0.01%),可提高涂料的阻燃性,当氧化石墨烯含量在0.005%时,涂层的耐燃时间可达432 s,炭层膨胀高度较未加氧化石墨烯涂层增加了13.04%。结合红外光谱(FT-IR)、X射线衍射(XRD)和扫描电子显微镜(SEM)等表征手段对炭层形貌进行分析可知,加入氧化石墨烯后炭层在300~500 ℃范围的热稳定性提高,燃烧炭层完整密实,隔热性能提高,耐燃时间提高。     

聚磷酸铵与次磷酸铝的共微胶囊制备及其在阻燃聚丙烯中的应用

以三聚氰胺-甲醛树脂（MF）为囊材、聚磷酸铵（APP）和次磷酸铝（AHP）为芯材,制备出共微胶囊化阻燃剂M（A-A）。通过傅里叶变换红外光谱、扫描电子显微镜及溶解度测试等方法来表征MF的包覆效果;采用垂直燃烧测定仪、极限氧指数仪和锥形量热仪等设备考察M（A-A）对聚丙烯（PP）的阻燃效果;通过冲击和拉伸实验对复合材料的力学性能进行表征。结果表明,MF树脂成功包覆并有效提高了A-A的耐水性能;添加相同质量的M（A-A）和A-A,前者明显降低热释放速率（R_HRR）和总热释放量（H_THR）,对PP的阻燃效果更好。添加阻燃剂后,复合材料的冲击强度先提高后降低,经过微胶囊化处理的阻燃剂对材料的拉伸性能损伤更小。     

酚醛改性丙烯酸树脂饰面型防火涂料

以酚醛改性丙烯酸树脂为成膜物质,加入阻燃协效剂和硅酸铝,制备了饰面型防火涂料。采用正交试验法,考察了硅酸铝、阻燃协效剂及酚醛树脂用量等因素对防火涂料耐燃时间的影响,依据GB 12441—2005测试了涂料的理化性能和防火性能。实验结果表明,各因素对耐燃时间影响程度由大到小依次为:填料、阻燃协效剂、酚醛树脂;涂料各组分最佳用量为:硼酚醛树脂34%、丙烯酸树脂42%、阻燃协效剂10%、硅酸铝14%。涂料的各项理化性能指标均已达到或超过国家标准的要求,附着力达到1级,耐冲击性40 cm,耐燃时间43 min。     

可膨胀石墨改性氯醚树脂钢结构防火涂料的研究

以氯醚树脂、丙烯酸树脂为成膜物,聚磷酸铵(APP)、季戊四醇(PER)、三聚氰胺(EN)为阻燃发泡体系,通过添加可膨胀石墨,提高了防火涂料炭质层的质量和热稳定性.研制出一种具有良好的附着力、耐候性及阻燃性的超薄膨胀型钢结构防火涂料,该防火涂料遇火涂层发泡膨胀,形成具有一定高度的密实微孔状阻燃层.     

Preparation and Application of Deformable and Orientable Intumescent Flame Retardants Incorporated with Polypropylene

An environment-friendly and easily operational method, reactive extrusion was adopted to prepare intumescent flame retardant (IFR), melamine salt of pentaerythritol phosphate (MPP) with special rheological properties. The outstanding advantage of the extruded MPP is that the flame retardant can deform, orientate and form fibrillar morphology in resin matrix during the incorporation with PP, however, conventional MPP can only solid-state disperse in PP melt phase and obtain granulated morphology. The deformation and orientation mechanism of the extruded MPP were researched by scanning electron microscope (SEM) and differential scanning calorimeter (DSC). It proved that this fibrillar morphology of the flame retardant obviously improved the flame retardancy and mechanical performance of PP.     

Preparation and characterization of microcapsulated red phosphorus and its flame‐retardant mechanism in halogen‐free flame retardant polyolefins

Microcapsulated red phosphorus (MRP), with a melamine–formaldehyde resin coating layer, was prepared by two‐step coating processes. The physical and chemical properties of MRP were characterized by Fourier‐transform infrared spectroscopy (FTIR), X‐ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM) and other measurements. The flame retardant action and mechanism of MRP in the halogen‐free flame retardant (HFFR) polyolefins (PO) blends have been studied using cone calorimeter, limiting oxygen index (LOI), thermogravimetric analysis (TGA) and dynamic FTIR spectroscopy. The results show that the MRP, which is coated with melamine–formaldehyde resin, has a higher ignition point, a considerably lower amount of phosphine evolution and of water absorption compared with red phosphorus (RP) itself. The data observed by cone calorimeter, LOI and TGA measurements from the PO/HFFR blends demonstrated that the MRP can decrease the heat release rate and effective heat of combustion, and increase the thermostability and LOI values of PO materials. The dynamic FTIR results revealed the flame‐retardant mechanism that RP can promote the formation of charred layers with the P–O and P–C complexes in the condensed phase during burning of polymer materials. Copyright © 2003 Society of Chemical Industry