EPS填充的三聚氰胺甲醛树脂基固体浮力材料的制备

以三聚氰胺与甲醛为原料,制备了三聚氰胺甲醛树脂,采用间歇法工艺将发泡聚苯乙烯(EPS)微球填充到三聚氰胺甲醛树脂基体中制备了三聚氰胺甲醛树脂基固体浮力材料,对浮力材料的断面微观结构、力学性能、吸水率和压缩强度进行了测试与分析,并对影响浮力材料密度的EPS微球粒径和影响浮力材料储能模量的EPS微球含量进行了研究。结果表明:随着静水压力的增加,固体浮力材料的吸水率增大,当静水压力超过80 MPa时,固体浮力材料结构受到明显破坏,吸水率急剧上升;该固体浮力材料的水下性能良好,力学性能和动态力学性能也符合基础应用要求。

Lateral earth pressure of granular backfills on retaining walls with expanded polystyrene geofoam inclusions under limited surcharge loading

Existing studies have focused on the behavior of the retaining wall equipped with expanded polystyrene(EPS)geofoam inclusions under semi-infinite surcharge loading rather than limited surcharge loading.In this paper,the failure mode and the earth pressure acting on the rigid retaining wall with EPS geofoam inclusions and granular backfills(henceforth referred to as EPS-wall),under limited surcharge loading are investigated through two-and three-dimensional model tests.The testing results show that different from the sliding of almost all the backfill in the EPS-wall under semi-infinite surcharge loading,only an approximately triangular backfill slides in the wall under limited surcharge loading.The distribution of the lateral earth pressure on the EPS-wall under limited surcharge loading is non-linear,and the distribution changes from the increase of the wall depth to the decrease with the increase of the limited surcharge loading.An approach based on the force equilibrium of a differential element is developed to predict the lateral earth pressure behind the EPS-wall subjected to limited surcharge loading,and its performance was fully validated by the three-dimensional model tests.

Performance Evaluation of Novel Eco-Materials Composed of Millet Husks, Rice Husks, and Polystyrene

Managing agricultural waste and expanded polystyrene (EPS) poses significant environmental and economic challenges. This study aims to create composites from millet husks, rice husks, and recycled EPS, using a manufacturing method that involves dissolving the polystyrene in a solvent followed by cold pressing. Various particle sizes and two binder dosages were investigated to assess their influence on the physico-mechanical properties of the composites. The mechanical properties obtained range from 2.54 to 4.47 MPa for the Modulus of Rupture (MOR) and from 686 to 1400 MPa for the Modulus of Elasticity in Bending (MOE). The results indicate that these composites have potential for applications in the construction sector, particularly for wood structures and interior decoration. Moreover, surface treatments could enhance their durability and mechanical properties. This research contributes to the valorization of agricultural and plastic waste as eco-friendly and economical construction materials.

Study of Rice Husks and Expanded Polystyrene Composites for Construction Applications

In the current context of environmental challenges, this study focuses on developing innovative and eco-friendly composites using rice husk and recycled expanded polystyrene. This dual-responsibility approach valorizes a by-product like rice husk, often considered waste, and reuses polystyrene, a plastic waste, thereby contributing to CO2 emission reduction and effective waste management. The manufacturing process involves dissolving recycled polystyrene into a solvent to create a binder, which is then mixed with rice husk and cold-compacted into composite materials. The study examines the impact of two particle sizes (fine and coarse) and different proportions of recycled polystyrene binder. The results show significant variations in the mechanical characteristics of the composites, with Modulus of Rupture (MOR) values varying from 2.41 to 3.47 MPa, Modulus of Elasticity (MOE) ranging from 223.41 to 1497.2 MPa, and Stiffness Coefficient (K) from 5.04 to 33.96 N/mm. These characteristics demonstrate that these composites are appropriate for various construction applications, including interior decoration, panel claddings, and potentially for furniture and door manufacturing when combined with appropriate coatings. This study not only highlights the recycling of agricultural and plastic waste but also provides a localized approach to addressing global climate change challenges through the adoption of sustainable building materials.

膨胀珍珠岩掺量对EPS泡沫混凝土性能的影响

为了解决建筑制冷、保暖所产生的建筑能源损耗问题,本文设计了一种新型、绿色、轻质、高强自保温泡沫混凝土砌块,即将聚苯乙烯(EPS)颗粒和膨胀珍珠岩颗粒这2种隔热轻质骨料与泡沫混凝土混合制成一种新型复合泡沫混凝土,并通过测试该复合混凝土的干密度、抗压强度、孔隙率、吸水率、导热系数、含水率和燃烧质量损失率,探讨膨胀珍珠岩掺量对复合泡沫混凝土性能的影响﹒研究结果表明:一定掺量膨胀珍珠岩能增加EPS泡沫混凝土的抗压强度,降低导热系数和燃烧质量损失率,且当膨胀珍珠岩掺量为12%时,其抗压强度最高为1.66 MPa;当膨胀珍珠岩掺量为21%时,其导热系数最低为0.133 W/(m·K);当膨胀珍珠岩掺量为18%时,其燃烧质量损失率最低为4.2%;当膨胀珍珠岩掺量为6%时,该配比满足A6等级,其干密度、导热系数和抗压强度等级达到C1,吸水率等级达到W10,燃烧性能等级达到A级不燃。

An Effective Green Porous Structural Adhesive for Thermal Insulating,Flame-Retardant,and Smoke-Suppressant Expandable Polystyrene Foam

To develop an efficient way to overcome the contradiction among flame retardancy,smoke suppression,and thermal insulation in expanded polystyrene(EPS)foams,which are widely used insulation materials in buildings,a novel"green"porous bio-based flame-retard ant starch(FRS)coating was designed from starch modified with phytic acid(PA)that simultaneously acts as both a flame retardant and an adhesive.This porous FRS coating has open pores,which,in combination with the closed cells formed by EPS beads,create a hierarchically porous structure in FRS-EPS that results in superior thermal insulation with a lower thermal conductivity of 27.0 mW·(m·K)^(-1).The resultant FRS-EPS foam showed extremely low heat-release rates and smoke-production release,indicating excellent fire retardancy and smoke suppression.The specific optical density was as low as 121,which was 80.6%lower than that of neat EPS,at 624.The FRS-EPS also exhibited self-extinguishing behavior in vertical burning tests and had a high limiting oxygen index(LOI)value of 35.5%.More interestingly,after being burnt with an alcohol lamp for 30 min,the top side temperature of the FRS-EPS remained at only 140℃with ignition,thereby exhibiting excellent fire resistance.Mechanism analysis confirmed the intumescent action of FRS,which forms a compact phosphorus-rich hybrid barrier,and the phosphorus-containing compounds that formed in the gas phase contributed to the excellent flame retardancy and smoke suppression of FRS-EPS.This novel porous biomass-based FRS system provides a promising strategy for fabricating polymer foams with excellent flame retardancy,smoke suppression,and thermal insulation.

Novel EPS/TiO2 Nanocomposite Prepared from Recycled Polystyrene

The synthesis and characterization of a new nanocomposite material that was prepared from recycled expanded polystyrene (EPS) and titanium dioxide (TiO2) is reported here. The EPS was obtained from chemical reagent box insulation. To obtain the nanocomposite, these materials were dispersed in a solvent, mixed with TiCl4 and heated. The resulting new material was characterized with SEM, TEM, TGA, BET, Raman and IR techniques. The Raman and IR spectra provided complementary information regarding the structure of the nanocomposite. The Raman spectra were used to identify the crystalline structure of TiO2 in the nanocomposite. In contrast, the IR spectra were used to identify the organic portion of the nanocomposite. The TEM images indicated that the nanocomposites had an average particle size of 6 - 12 nm. In addition, the adsorption and photocatalytic properties of the new material were evaluated. The EPS/TiO2 nanocomposite was efficient at degrading methylene blue (MB) dye solutions under UV irradiation. Furthermore, according to thermal analysis, this material had greater polymer stability due to the incorporation of TiO2.

EPS颗粒改良膨胀土强度试验研究

选取湖北某边坡工程膨胀土为试验对象,在保持最大干密度和最优含水率的条件下,通过全自动三轴仪对不同掺量的EPS颗粒改良膨胀土进行三轴试验,探究了不同掺量的EPS颗粒与膨胀土抗剪强度间的关系。结果表明:土样主应力差值先快速增加后缓慢增加达到峰值后下降并稳定;素土样峰值强度最大;随着EPS颗粒掺量增加,土样的强度、黏聚力和内摩擦角都有变小的趋势;当掺量超过10%时,改良膨胀土的强度变化不明显;对比黏聚力、内摩擦角和掺量关系曲线表明黏聚力变化比内摩擦角更明显,说明黏聚力受掺量变化影响较大;通过拟合可得到黏聚力、内摩擦角与掺量的关系式。

发泡聚苯乙烯颗粒流化热解特性的实验研究

基于不同加热速率下的热重测试,计算发泡聚苯乙烯颗粒的热裂解动力学参数,自建可视化流化热解炉研究流化床热解过程,并对产物进行分析。热重实验数据根据阿伦尼乌斯方程用KAS,OFW,CR方法计算活化能和指前因子等热解动力学参数。通过可视化实验观察分析不同温度下发泡聚苯乙烯颗粒热解过程的形态变化,并分析固、液、气三相产物的主要成分。KAS和OFW方法计算的活化能分别为143.55 kJ/mol和147.21 kJ/mol。CR方法计算指前因子为6.79×10^(5)~4.40×10^(8)min^(-1)。发泡聚苯乙烯热解过程中吉布斯自由能为219.30 kJ/mol,反应焓变为137.94 kJ/mol,熵变为-0.12 kJ/K。流化裂解产物主要是苯乙烯、1,3,5-三苯基环己烷、9,9-二甲基萘为主的裂解油、碳黑及甲苯和苯乙烯为主的裂解气。

EPS颗粒混合轻质土的施工技术及其应用实例

EPS颗粒混合轻质土是一种轻质、高强、环保、经济的新型土工材料,但国内还未见工程应用的报道。通过在新安江电厂88—70开关站交通道路工程中的应用实践,探讨了EPS颗粒混合轻质土的施工技术,证实了该材料可以起到缩短工期和提高工程安全性的目的。

EVA改性EPS混凝土微观结构及性能研究

为了改善聚苯乙烯(EPS)轻集料混凝土中EPS颗粒与水泥砂浆界面的黏结性能,提高EPS轻集料混凝土的力学性能,采用乙烯-醋酸乙烯酯(EVA)乳液对EPS颗粒表面进行改性,并对改性前后EPS轻集料混凝土的力学性能作了对比试验,结合扫描电镜、X射线衍射和红外光谱,分析了EVA乳液对EPS轻集料混凝土性能的影响机理.结果表明:EVA改性改善了EPS轻集料混凝土的微观结构,使其内部孔洞数量减少,孔洞尺寸趋于减小;使水泥水化更为充分,水化产物组成得以优化,EPS轻集料混凝土的180 d抗压强度和抗折强度得到提高.

废弃聚苯乙烯泡沫(EPS)外墙外保温砂浆研究

通过改性,EPS表面由憎水性变为亲水性,能被新拌硅酸盐水泥浆体所润湿。以改性EPS为轻骨料,水泥为胶结材,辅以纤维和聚合物改性,可配制施工性、热工性、耐候性、抗裂性良好的保温砂浆。这种新型保温砂浆可用于外墙外保温,突破了传统保温砂浆只能作内保温的局限,已在建筑工程中大规模应用。

EPS轻质混凝土性能研究

采用类似“裹砂”工艺的预拌方法拌制发泡聚苯乙烯(EPS)轻质混凝土并测试其力学性能.结果表明:用EPS颗粒部分取代粗集料和细集料,可以制得表观密度为800-1 800 kg/m3、抗压强度达11-20 MPa的EPS轻质混凝土;微硅粉能显著改善EPS颗粒与水泥浆体的粘结性能,提高EPS轻质混凝土抗压强度,而掺入钢纤维则能显著改善其干缩性能.

基于EPS减荷措施的高填涵洞试验研究

通过大型高填方涵洞原位减荷试验,对采用EPS减荷材料下的土压力和位移进行了监测,将未减荷情况与不同厚度EPS减荷情况下的结果进行了对比分析,并采用Marc有限元分析软件对其进行了数值仿真,研究了EPS材料的减荷特性及减荷后涵洞结构相关性状的变化规律。结果表明:EPS减荷效果显著,减荷后涵洞结构受力有所改善,为工程设计与施工提供了有效的指导和参考依据。

密度和应变率对聚苯乙烯泡沫(EPS)准静态压缩力学行为的影响

分别研究了聚苯乙烯泡沫(Expanded polystyrene,简称EPS)在三种不同密度和三种不同加载速率下的无侧限单轴准静态压缩力学行为。结果表明:EPS的压缩与一般多孔材料的压缩特征相似,其应力-应变曲线也分为三阶段(弹性段、塑性屈服平台段及致密段)。并验证了聚苯乙烯泡沫(EPS)在线弹性阶段的弹性模量与其密度近似符合二次函数关系;通过对实验结果的拟合得出了EPS的密度与其屈服强度呈线性关系并给出了关系表达式。同时表明:同一密度的EPS在不同加载速率下其线弹性模量基本不变而屈服强度随加载速率的增加而显著增加,其应变率敏感度m值较大且变化显著,EPS表现出明显的应变率效应。

EPS保温砂浆研制及施工工艺

EPS保温砂浆的抗裂性、耐候性优良 ,可用于外保温 ,本文介绍它的性能和施工工艺。

EPS颗粒对混凝土的增韧效应

配制了聚苯乙烯(EPS)颗粒体积分数分别为10%,20%,30%,40%,50%的EPS混凝土,采用100分离式霍普金森压杆(SHPB)试验装置,以比能量吸收作为指标,研究了EPS颗粒对混凝土的增韧效应,探讨了EPS颗粒对混凝土的增韧机理.结果表明:冲击荷载作用下,由于应变率效应,相同体积分数的EPS混凝土冲击韧性随应变率的增加而提高,具有显著的应变率相关性;由于EPS颗粒的微结构效应,在EPS颗粒体积分数为10%～30%时,其韧性较未掺EPS颗粒的混凝土有不同程度的提高,EPS颗粒体积分数为20%时对混凝土韧性的改善效果最佳.当EPS颗粒体积分数达到40%～50%时,其韧性有所降低.

EPS表面改性及其保温砂浆的耐候性与抗裂性

EPS表面为憎水性 ,无机胶凝材对其不润湿。在新拌砂浆中 ,由于EPS颗粒与水泥浆体之间不亲合 ,且容重很小 ,所以在搅拌过程中很容易造成EPS颗粒“上浮” ,从而导致砂浆分层 ,保水性下降 ,严重影响其和易性与施工性能。通过对EPS预处理 ,使其表面由憎水性变为亲水性 ,使之能被新拌硅酸盐浆体所润湿。EPS表面改性的技术途径为 :选择适宜的高分子粘结剂和偶联剂 ,配制低水灰比的聚合物硅酸盐胶凝材 ,利用粘结剂和偶联剂的双重作用 ,通过复合胶凝材对EPS的表面包裹 ,在EPS表面形成亲水性硅酸盐薄壳 ,实现EPS表面改性。以改性EPS为轻骨料 ,水泥为胶结材 ,纤维和聚合物改性可配制施工性、热工性、耐候性、抗裂性良好的保温砂浆。这种新型保温砂浆可用于外墙外保温 ,突破了传统保温砂浆只能作内保温的局限 ,已在建筑节能示范工程中大规模应用。

MPC-EPS轻质混凝土性能试验研究

以磷酸镁水泥（magnesium phosphate cement,MPC）为胶凝材料制备出了表观密度为1800-750 kg/m3的可用于结构的磷酸镁水泥-聚苯乙烯泡沫（MPC-EPS）混凝土.试验研究了MPC-EPS混凝土的力学性能、干缩性能、吸水率及抗冻融和干湿循环能力.结果表明：MPC-EPS混凝土具有较高的早期强度,且EPS掺量越大,其早期强度发展越快;与普通水泥为胶凝材料的EPS混凝土相比,MPC-EPS混凝土具有较低的干缩变形和吸水率,是一种耐久性良好的保温隔热材料.

EPS轻质节能混凝土砌块砌体抗压性能研究

可发性聚苯乙烯(简称EPS)轻质节能混凝土砌块是为替代实心粘土砖而自主研发的一种新型墙体材料,因该砌块与普通混凝土砖在材料性质和制作工艺等方面有差异,作为承重墙体砌块使用时,《砌体结构设计规范》(GB50003-2011)中砌体抗压强度计算公式不合适。为得到适用于该砌体的计算公式并使产品推广使用,特取强度等级为MU5、MU15的EPS混凝土砌块,设计8组24个受压构件,开展砌体抗压性能试验研究,并通过实验研究、理论分析、经验回归,推导得出EPS砌块砌体抗压承载力计算公式为fm1=1.182f_1^(0.407)(1+0.07f_2),EPS混凝土砌块砌体弹性模量计算公式建议采用E_1=147.1f_m(f_m)~1/2(承重砌块砌体)和E_2=175.6f_m(f_m)~1/2( 自承重砌块砌体),而泊松比的取值建议采用0.190(承重砌块砌体)和0.220(自承重砌块砌体)。