scholarly journals A High-Performance and Low-Cost Soy Flour Adhesive with a Hydroxymethyl Melamine Prepolymer

Polymers ◽  
2018 ◽  
Vol 10 (8) ◽  
pp. 909 ◽  
Author(s):  
Meng Zhang ◽  
Yi Zhang ◽  
Mingsong Chen ◽  
Qiang Gao ◽  
Jianzhang Li
Keyword(s):  
Thermal Stability ◽  
Shear Strength ◽  
High Performance ◽  
Water Resistance ◽  
Low Cost ◽  
Soy Flour ◽  
National Standard ◽  
Interpenetrating Network ◽  
Residual Rate ◽  
Rate Functions

To improve the performance of a soy flour (SF)-based adhesive, a low-cost hydroxymethyl melamine prepolymer (HMP) was synthesized and then used to modify the SF-based adhesive. The HMP was characterized, and the performance of the adhesive was evaluated, including its residual rate, functions, thermal stability, and fracture section. Plywood was fabricated to measure wet shear strength. The results indicated that the HMP preferentially reacted with polysaccharose in SF and formed a cross-linking network to improve the water resistance of the adhesive. This polysaccharose-based network also combined with the HMP self-polycondensation network and soy protein to form an interpenetrating network, which further improved the water resistance of the adhesive. With the addition of 9% HMP, the wet shear strength (63 °C) of the plywood was 1.21 MPa, which was 9.3 times that of the SF adhesive. With the HMP additive increased to 15%, the shear strength (100 °C) of the plywood was 0.79 MPa, which met the plywood requirement for exterior use (≥0.7 MPa) in accordance with Chinese National Standard (GB/T 9846.3-2004). With the addition of 9% and 15% HMP, the residual rates of the adhesive improved by 5.1% and 8.5%, respectively. The dense interpenetrating network structure improved the thermal stability of the resultant adhesive and created a compact fracture to prevent moisture intrusion, which further increased the water resistance of the adhesive.

scholarly journals Development of a High-Performance Adhesive with a Microphase, Separation Crosslinking Structure Using Wheat Flour and a Hydroxymethyl Melamine Prepolymer

Polymers ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 893 ◽  
Author(s):  
Jieyu Zhang ◽  
Yi Zhang ◽  
Jianzhang Li ◽  
Qiang Gao
Keyword(s):  
Shear Strength ◽  
Fracture Surface ◽  
Bond Strength ◽  
Wheat Flour ◽  
High Performance ◽  
Water Resistance ◽  
Microphase Separation ◽  
Low Cost ◽  
Bond Performance ◽  
Effective Manner

The objective of this study is to use wheat flour (WF) and hydroxymethyl melamine prepolymer (HMP) to develop a low cost, highly water-resistant, starch-based bio-adhesive for plywood fabrication. Three-layer plywood was fabricated using the resultant adhesive, and the wet shear strength of the plywood samples was measured under various conditions. After determining that water resistance was significantly improved with the addition of HMP, we evaluated the physical characteristics of the starch-based adhesive and functional groups and analyzed the thermal stability and fracture surface of the cured adhesive samples. Results showed that by adding 20 wt.% HMP into WF adhesive, the sedimentation volume in the resultant adhesive decreased by 11.3%, indicating that the increase of crosslinking in the structure of the adhesives increased the bond strength, and the wet shear strength of the resultant plywood in 63 °C water improved by 375% when compared with the WF adhesive. After increasing the addition of HMP to 40 wt.%, the wet shear strength of the resultant plywood in 100 °C water changed from 0 MPa to 0.71 MPa, which meets the exterior use plywood requirement. This water resistance and bond strength improvement resulted from (1) HMP reacting with functions in WF and forming a crosslinking structure to prevent moisture intrusion; and (2) HMP self-crosslinking and combining with crosslinked WF to form a microphase separation crosslinking structure, which improved both the crosslinking density and the toughness of the adhesive, and subsequently, the adhesive’s bond performance. In addition, the microphase separation crosslinking structure had better thermostability and created a compact ductile fracture surface, which further improved the bond performance of the adhesive. Thus, using a prepolymer to form a microphase separation crosslinking structure within the adhesive improves the rigidity, toughness, and water resistance of the material in a practical and cost-effective manner.

Advances in preparation, modification, and application of polypropylene membrane

2016 ◽  
Vol 36 (4) ◽  
pp. 329-362 ◽  
Author(s):  
Nurul F. Himma ◽  
Sofiatun Anisah ◽  
Nicholaus Prasetya ◽  
I Gede Wenten
Keyword(s):  
Thermal Stability ◽  
High Performance ◽  
Chemical Resistance ◽  
Low Cost ◽  
Comprehensive Overview ◽  
Preparation Methods ◽  
Good Thermal Stability ◽  
Polypropylene Membrane ◽  
Membrane Fabrication ◽  
Potential Applications

Abstract Polypropylene (PP) is one of the most used polymers for microporous membrane fabrication due to its good thermal stability, chemical resistance, mechanical strength, and low cost. There have been numerous studies reporting the developments and applications of PP membranes. However, PP membrane with high performance is still a challenge. Thus, this article presents a comprehensive overview of the advances in the preparation, modification and application of PP membrane. The preparation methods of PP membrane are firstly reviewed, followed by the modification approaches of PP membrane. The modifications includes hydrophilic and superhydrophobic modification so that the PP membranes become more suitable to be applied either in aqueous applications or in non-aqueous ones. The fouling resistant of hydrophilized PP membrane and the wetting resistant of superhydrophobized PP membrane are then reviewed. Finally, special attention is given to the various potential applications and industrial outlook of the PP membranes.

Blue-emitting butterfly-shaped donor–acceptor-type 1,3,5,9-tetraarylpyrenes: easily available, low-cost conventional fluorophores for high-performance near ultraviolet electroluminescence with CIEy < 0.05

2021 ◽  
Vol 9 (1) ◽  
pp. 260-269
Author(s):  
Huijuan Ran ◽  
Zhen Zhao ◽  
Xuewei Duan ◽  
Fuli Xie ◽  
Ruijun Han ◽  
...  
Keyword(s):  
Thermal Stability ◽  
High Performance ◽  
Low Cost ◽  
Good Thermal Stability ◽  
Near Ultraviolet ◽  
Donor Acceptor ◽  
Blue Emitters

Three donor–acceptor (DA)-type pyrene-based blue emitters with good thermal stability and their applications in NUV OLEDs are demonstrated.

Optimization of Processing Variables in Wheat Straw Particleboard for Manufacturing Pallets

2012 ◽  
Vol 200 ◽  
pp. 335-338 ◽  
Author(s):  
Peng Luo ◽  
Chuan Min Yang ◽  
Hong Wei Ji
Keyword(s):  
Wheat Straw ◽  
Steam Explosion ◽  
High Performance ◽  
Low Cost ◽  
Urea Formaldehyde ◽  
National Standard ◽  
Hot Press ◽  
Board Density ◽  
Press Temperature ◽  
Uf Resin

The goal of this work was to make particleboards for manufacturing pallets from wheat straw using low cost urea formaldehyde (UF) resin adhesive. The wheat straws were subject to steam explosion pretreatment to improve bondability with UF resin. Particleboards were obtained from the steam explosion pretreated wheat straws with UF resin. Particleboard manufacturing parameters, such as pressing time, temperature and board density, were optimized to achieve high performance panel board for pallets. The optimum parameters were found to be: hot press temperature 170 °C, hot press time 40 s/mm, resin application ratio 10%, and straw particle size 12 mm. Under the optimum conditions particleboards met the mechanical requirements for the industrial use particleboards based on the Chinese National Standard for Particleboard and were able to make pallets.

scholarly journals Metal Coordination Bonds Crosslinked Polydopamine/Cellulose Nanofibril Composite Aerogels with Significantly Improved Thermal Stability, Flame Resistance, and Thermal Insulation Properties

2021 ◽  
Author(s):  
Fuyi Han ◽  
Hong Huang ◽  
Yan Wang ◽  
Lifang Liu
Keyword(s):  
Thermal Stability ◽  
Thermal Insulation ◽  
High Performance ◽  
Low Cost ◽  
Metal Coordination ◽  
Cellulose Nanofibril ◽  
Flame Resistance ◽  
Comprehensive Properties ◽  
Composite Aerogels ◽  
Coordination Bonds

Abstract Cellulose nanofibril (CNF) aerogels have attracted great interests in recent years due to the low cost, sustainability and biocompatibility of raw CNFs. However, the poor thermal stability and flammable feature of CNF aerogels have limited their wider applications. In this paper, polydopamine/CNF composite aerogels with good comprehensive properties are fabricated by modification of CNF with polydopamine and metal coordination bonds crosslinking. The microstructure and properties of composite aerogels are thoroughly characterized by a variety of tests. It is found that the microstructure of aerogels are more regular and the compressive strength of aerogels are enhanced by the incorporation of polydopamine and Fe3+ crosslinking. Importantly, the thermal stability and flame resistance of aerogels are significantly improved, which permit the application of composite aerogels in high-temperature thermal insulation. In addition, the reversible characteristic of metal coordination bonds allows the water induced healing of fractured composite aerogels. This study is expected to provide information for future development of green and high-performance aerogels.

scholarly journals Radiation Modification and Characterization of Polyvinyl alchohol/Starch/Citric Acid/Glycerol Bioblend Film

2021 ◽  
Author(s):  
Ashraf M. Abdel Ghaffar ◽  
H. E. Ali
Keyword(s):  
Thermal Stability ◽  
Citric Acid ◽  
Water Resistance ◽  
Low Cost ◽  
Cost Effective ◽  
Hydroxyl Groups ◽  
Mechanical And Thermal Properties ◽  
Packaging Films ◽  
Potential Development ◽  
Radiation Modification

Abstract The blending of polyvinyl alcohol (PVA) with starch with different content of citric acid as crosslinker and glycerol as plasticizer were performed by casting method. The hydroxyl groups of PVA and Starch react with the citric acid (1 %) and glycerol (10 vol %) to form crosslinked network. The FTIR spectral analyses show the successful preparation of the different composition of the prepared PVA/ Starch /Citric acid/Glycerol bioblend films. It is found that the prepared PVA/ Starch /Citric acid/Glycerol with composition (2:1:1/10 vol %) bioblend film characterized by higher water resistance, good mechanical and higher thermal stability than other prepared bioblend films. The using of gamma radiation improved and modified water resistance property were the water uptake at equilibrium reduced remarkably at dose of 10 kGy. Also the thermal stability increased as irradiation dose increased up to dose of 30 kGy The improved mechanical and thermal properties of the selected PVA/ Starch /Citric acid/Glycerol with composition (2:1:1/10 vol %) bioblend film were compared with LDPE and PP packaging films and found to be competitive to the these commercially packaging films which are also nonbiodegradable synthetic polymers than the prepared selected PVA/ Starch /Citric acid/Glycerol with composition (2:1:1/10 vol %) bioblend film. Hence this study can be represent potential development of low cost-effective and modified PVA/ Starch /Citric acid/Glycerol with composition (2:1:1/10 vol %) bioblend film that characterized by several advantages over the commercially available petrochemical films and can be used in different applications such as packaging industry.

High Performance Anisotropic Conductive Adhesives Using Copper Particles With an Anti-Oxidant Coating Layer

2010 ◽  
Vol 132 (1) ◽  
Author(s):  
Myung Jin Yim ◽  
Yi Li ◽  
Kyoung Sik Moon ◽  
C. P. Wong
Keyword(s):  
Thermal Stability ◽  
Coupling Agent ◽  
High Performance ◽  
Low Cost ◽  
Particle Surface ◽  
Surface Characteristics ◽  
Conductive Adhesives ◽  
Element Analysis ◽  
Copper Surfaces ◽  
Thermal Stability Of

This paper describes the development and characterization of anisotropically conductive films (ACFs) incorporated with copper (Cu) particles as electrically conductive fillers for environmentally friendly, low cost, high electrical, and high thermal interconnect applications in microelectronics packaging. The Cu particle surface modification by a coupling agent and its effects on the electrical conductivity and thermal stability of Cu-filled ACF joints were investigated for the potential alternatives of conventional Au-coated polymer and Au-coated Ni-filled ACFs. The surface characteristics of a thin film of the coupling agent on copper surfaces such as element analysis, their hydrophobicity, and thermal stability were evaluated. The treated Cu ball-filled ACF showed the lowest contact resistance 1.0×10−5 Ω, higher current carrying capability, and higher thermal stability of ACF joints compared with the conventional Au-coated polymer ball and Au-coated Ni ball-filled anisotropically conductive adhesives.

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