Resin Blends Research Articles

Modelling the Stiffness-Temperature Dependence of Resin-Rubber Blends Cured by High-Energy Electron Beam Radiation Using Global Search Genetic Algorithm.

Modelling the influence of high-energy ionising radiation on the properties of materials with polymeric matrix using advanced artificial intelligence tools plays an important role in the research and development of new materials for various industrial applications. It also applies to effective modification of existing materials based on polymer matrices to achieve the desired properties. In the presented work, the effects of high-energy electron beam radiation with various doses on the dynamic mechanical properties of melamine resin, phenol-formaldehyde resin, and nitrile rubber blend have been studied over a wide temperature range. A new stiffness-temperature model based on Weibull statistics of the secondary bonds breaking during the relaxation transitions has been developed to quantitatively describe changes in the storage modulus with temperature and applied radiation dose until the onset of the temperature of the additional, thermally-induced polymerisation reactions. A global search real-coded genetic algorithm has been successfully applied to optimise the parameters of the developed model by minimising the sum-squared error. An excellent agreement between the modelled and experimental data has been found.

Maleimide end- capped polyether telechelics as novel toughening agents for unsaturated polyester resin

This paper deals with a study on toughening of an unsaturated polyester resin (UPR) using maleimide end-capped oligomers of polypropylene glycol (M-PPG), polytetramethyene oxide (M-PTMO), and polyethylene glycol (M-PEG) of varying molecular weights. These macro bismaleimides with large spacing between the functional groups were synthesized from the corresponding polyols (hydroxy telechelics) by reaction with (4-Maleimido) benzoyl chloride (MBC). These derivatives were characterised by chemical and spectral methods. These were then blended and co-cured with a UP resin based on copoly-propylene glycol (terephthalate –maleate) and relying on maleic acid–styrene copolymerisation for curing. The impacts of the nature, concentration and molecular weight of the telechelic additive on the physical and mechanical properties of the resultant unsaturated polyester resin (UPR) blends have been examined. Addition of the telechelics improved the mechanical characteristics of the crosslinked systems significantly. The improvement in fracture properties for a telecheilc was directly correlatable to a decrease in overall crosslink density estimated exprimentally as well as theoretically. The additive’s backbone structure dictated the Tg and related properties of the blend. The properties were found to be the best for the blend toughened with M-PPG with a molecular weight 2000 g/mol, at 2.5 parts per hundred parts.The morphological features at this concentration as reflected in scanning electron microscopic analyses showed descrete poly ether particles microphase separation in the UPR matrix that acted as a crack path arrester.

Assessment of the physical characteristics and fishing performance of gillnets using biodegradable resin (PBS/PBAT and PBSAT) to reduce ghost fishing

Abstract Ghost fishing is caused by derelict synthetic‐fibre nets that have been lost at sea. Thus, biodegradable nets have been developed with the aim of protecting marine ecosystems. The performance of biodegradable nets and their ability to replace conventional gillnets was assessed. Two types of biodegradable nets were used in the experiment: one made from a blended resin containing 90 wt% polybutylene succinate (PBS) and 10 wt% polybutylene adipate‐co‐terephthalate (PBAT) (Bio‐1), and the other made from a polybutylene succinate co‐adipate‐co‐terephthalate (PBSAT) resin (Bio‐2) with improved flexibility and physical homogeneity. For No. 3 monofilaments (standard diameter, Ø, 0.284 mm), Bio‐1 and Bio‐2 both showed a wet straight‐line breaking strength of around 99% that of polyamide (PA). For No. 2 monofilaments (Ø 0.200 mm), the wet straight‐line breaking strengths of Bio‐1 and Bio‐2 were 84.9 and 93.0% that of PA, respectively, indicating worse physical properties for Bio‐1 at No. 2 thickness. The wet knotted breaking strengths of No. 3 thickness Bio‐1 and Bio‐2 were 92.9 and 82.7% that of PA, respectively. The straight‐line breaking strength of Bio‐2 was 1.1 times that of Bio‐1. The wet knotted breaking strengths of Bio‐1 and Bio‐2 were 80.2 and 93.4% that of PA, respectively, and the knotted breaking strength of Bio‐2 was around 1.2 times that of Bio‐1. Regarding flexibility, for No. 3 thickness monofilaments, the mean wet stiffness values of PA, Bio‐1, and Bio‐2 were 9.50, 15.23, and 9.68 g, respectively, indicating that Bio‐2 was similar to PA and around 1.6 times softer than Bio‐1. The fishing performance, by weight, was PA > Bio‐2 > Bio‐1; however, the difference between PA and Bio‐2 was not statistically significant. Biodegradable nets may not be a perfect solution, but we believe that they can contribute greatly to reducing ghost fishing and protecting marine ecosystems.

A Study of Some Mechanical Properties of Composite Materials with a Dammar-Based Hybrid Matrix and Reinforced by Waste Paper.

When obtaining environment-friendly hybrid resins made of a blend of Dammar natural resin, in a prevailing volume ratio, with epoxy resin, it is challenging to find alternatives for synthetic resins. Composite materials reinforced with waste paper and matrix made of epoxy resin or hybrid resin with a volume ratio of 60%, 70% and 80% Dammar were studied. All samples obtained have been submitted to tensile tests and Scanning Electron Microscopy (SEM) analysis. The tensile response, tensile strength, modulus of elasticity, elongation at break and the analysis of the fracture surface were determined. The damping properties of vibrations of bars in hybrid resins and in the composite materials under study were also examined. The mechanical properties of the four types of resins and of the composite materials were compared. The chemical composition for a hybrid resin specimen were obtained using the Fourier Transformed Infrared Spectroscopy (FTIR) and Energy, Dispersive X-ray Spectrometry (EDS) analyzes.

Facile preparation and application performance evaluation of SBS/C9 petroleum resin blends as modifier for high viscosity asphalt

To reduce the cost of high viscosity asphalt, SBS/C9 petroleum resin blends (SPR) were prepared via a simple one-pot polymer alloying process as modifiers for high viscosity asphalt in this study. The chemical characteristics of SRP and its modification effect on asphalt were studied and also compared with the traditional modifier (Tafpack-Super, abbreviated as TPS). Results show that SPR modifier contains more oxygen-containing functional groups than the TPS modifier. The molecular weight of SPR modifier is slightly higher but distributes over a wider range than that of the TPS modifier. Besides, its melting and crystallization temperatures of SPR modifier are lower than those of TPS modifier, thus SPR modifier has better compatibility with asphalt during production, making SPR easier to be dispersed in asphalt with smaller average particle size. Due to these reasons, SPR modifier has better modification effect on asphalt than traditional TPS modifier. Besides, the price of self-made SPR can be reduced to 29% of that of commercial TPS modifier, and the raw materials price of high viscosity asphalt with SPR modifier can reduce to 48.8% of that with TPS modifier. Therefore, SPR is a good modifier for the preparation of high viscosity asphalt with high performance and low cost.

Tooth sealing formulation with bacteria-killing surface and on-demand ion release/recharge inhibits early childhood caries key pathogens.

Herein, we investigated a biointeractive tooth sealing material consisted of dimethylaminohexadecyl methacrylate (DMAHDM) and amorphous calcium phosphate nanoparticles (NACPs) to address the above issues simultaneously. Of note, 5% DMAHDM was incorporated into the resin blend, and 20% NACP was added to inorganic filler content of dental formulations intended as dental sealants. The sealing materials were used to seal human extracted teeth. The sealed teeth were subjected to an early childhood caries (ECC) key pathogen (Candida albicans and Streptococcus mutans) biofilm model using a dynamic caries tooth model (CDC reactor). The biofilm growth over the sealed teeth was assessed via colony-forming unit counting metabolic activity assays. The enamel surface hardness loss, degree of conversion, shear bond strength (SBS), and cytotoxicity were also investigated. Formulations having DMAHDM displayed antibacterial efficiency of 2.8-3.5 and 1.4-4.0 log inhibition for Streptococcus mutans and Candida albicans, respectively. Furthermore, the metabolic activity was reduced on the top of the sealed tooth with the biointeractive sealing materials (p < .05). The degree of conversion values was acceptable. The enamel surface hardness loss decreases (36 ± 9.8%) when in contact with the biointeractive tooth sealing material. The SBS of the combined formulation (5% DMAHDM + 20% NACP) was lower than commercial sealant but similar to experimental control. The investigated sealing material holds valuable dual antibacterial and antifungal activities associated with a reduced mineral loss against the cariogenic challenge promoted by ECC key pathogens.

Synthesis and characterization of divinylbenzene-based cyanate resin and its quartz fiber-reinforced composite

Cyanate ester (CE) resins are important polymeric materials with excellent dielectric properties, low moisture absorption, and good heat resistance, which have shown great superiority for use in electronic and aerospace industries. In this article, a novel CE resin was designed and synthesized from divinylbenzene. The proposed structures were characterized with Fourier transform infrared spectroscopy, gel permeation chromatography, and mass spectrometry. The chemical reaction activity, heat resistance, dielectric properties, and water adsorption of the synthesized CE derived from divinylbenzene (DVBCy) were examined and compared with the traditional bisphenol A and bisphenol M (4,4′-[1,3-phenylenebis(1-methyl-ethylidene)]bisphenol)-based CE. The DVBCy resin exhibits a glass transition temperature ( T g) of 162.7°C, a dielectric constant of 2.61, a dielectric loss tangent angle of 0.0035 at about 10 GHz, and a lower water absorption of 0.77%. Compared with the bisphenol M type CE, DVBCy resin provides slightly superior dielectric properties, higher mechanical properties, more favorable process technology for prepreg construction, and lower costing. The DVBCy blend resin modified with bisphenol A-based CE and core–shell particles possesses suitable rheological properties, and the corresponding quartz fiber-reinforced composite exhibits excellent mechanical as well as dielectric properties.

Polyetherketone powder/epoxy blends with low viscosity and high mechanical properties

The difficult forming process and construction caused by high viscosity has been the main problem restricting the application of high-performance thermoplastic/epoxy blends. In this contribution, low viscous polyetherketone (PEK)/diglycidyl ether of bisphenol A epoxy resin (DGEBA) blends were prepared by mixing the ultrafine PEK powder and DGEBA monomer at ambient temperature. Rheological behaviour shows that complex viscosity of the undissolved blends containing 20 wt% PEK powder is two orders of magnitude lower than that of the dissolved one. Interestingly, diffusion and phase separation of PEK powder in the undissolved PEK/DGEBA/2-methylimidazole/dicyandiamide (M-DICY) blends are affected by the curing processes. Phase-inverted morphology was observed after curing at 120°C/1h + 160°C/0.5 h for the undissolved 20 wt% PEK/DGEBA/M-DICY blends which also exhibited outstanding tensile strength and lap shear strength both at 298 and 77 K. We believe this work should provide a new insight into the preparation of advanced thermoplastic/epoxy blends.

KARAKTERISASI BESARAN MAGNET PERMANEN DARI HASIL CAMPURAN NdFeB DAN SERBUK EPOXY RESIN

The bonded permanent magnet Nd 2 Fe 14 B has been made using raw materials Nd-Fe-B powder mixed withadhesive epoxy resin . Permanent magnets can be applied as a component of small DC motors and car parts.NdFeB composition variation on epoxy resins are made with the ratio of 93 : 7, 95 : 5, 90 : 10, 80 : 20, 70 : 30, 60: 40, 50 : 50, (% weight). Raw material NdFeB was made from the mixture of Nd, Fe and B with atomic ratio 2 :14 : 1 by using mechanical alloying technique. The blend of NdFeB and epoxy resin has been done in the vacuumbox . Sample test was prepared by compression with hydraulic press pressure 100kg/cm 2 within 2 minutes. Heattreatment in the oven with a temperature of 180 O C for 4 hours. The sample test was made in cylindrical shape witha diameter of 2-3 cm and thickness of 0.4 to 0.9 cm. The measurement of density vs. Histerisis has been recorded.The results show that the bonded NdFeB permanent magnets achieve optimum conditions in comparison NdFeB97% and 3% epoxy with the density = 4.49 g/cm3 and remanansi (Br) = 5.32 kG, HcJ = 7.936 kOe and (BH) max= 5.75 MGOe.

Developing Highly Tough, Heat-Resistant Blend Thermosets Based on Silicon-Containing Arylacetylene: A Material Genome Approach.

Silicon-containing arylacetylene (PSA) resins exhibit excellent heat resistance, yet their brittleness limits the applications. We proposed using acetylene-terminated polyimides (ATPI) as an additive to enhance the toughness of the PSA resins and maintain excellent heat resistance. A material genome approach (MGA) was first established for designing and screening the acetylene-terminated polyimides, and a polyimide named ATPI was filtered out by using this MGA. The ATPI was synthesized and blended with PSA resins to improve the toughness of the thermosets. Influences of the added ATPI contents and prepolymerization temperature on the properties were examined. The result shows that the blend resin can resist high temperature and bear excellent mechanical properties. The molecular dynamics simulations were carried out to understand the mechanism behind the improvement of toughness. The present work provides a method for the rapid design and screening of high-performance polymeric materials.

Experimental study of the CTBN effect on mechanical properties and mode I and II fracture toughness of a new epoxy resin

Due to the high strength and adhesiveness of epoxies, these materials are widely used in various industries such as aerospace. But because of their inherent brittleness and poor fracture toughness, they do not have enough resistance against crack propagation. In adhesive joints, maximum stresses near the ends of the overlaps resulted in premature failure of the joints. In this study, for toughening the epoxy, carboxyl-terminated butadiene acrylonitrile (CTBN) as a liquid rubber was used. Blends of a new epoxy resin (R510) and the CTBN in several weight fractions were produced and characterized. In this article, four tests have been done to find the mechanical properties and mode I and II fracture toughness of the adhesives. The tensile and shear tests were performed to achieve Young’s modulus (E), maximum tensile stress (σf), shear modulus (G), maximum shear stress (τf) and Poisson’s ratio (ν) of the adhesives. Also, the double-cantilever beam (DCB) and end-notched flexure (ENF) tests were used to obtain the mode I fracture toughness (GIc) and mode II fracture toughness (GIIc), respectively. The results from each of the DCB and the ENF tests were analyzed by three different methods and compared. Results showed that by adding CTBN to epoxy, E, G, ν, σf and τf are reduced, but toughness, the resistance to crack growth and as a result, the GIc and GIIc increased efficiently. These data can be used to predict the adhesive joint strength and simulating the damage initiation and its evolution until failure with cohesive zone modeling (CZM).

Effect of water on impact strength of RTV silicon rubber / Thermosets blend reinforced with nanoparticles

Binary and ternary blends of epoxy resin (EP) and unsaturated polyester (UPE) with different weight fractions (0, 3, 5, 7, 10 and 20%) percentages of RTV silicone rubber (SR) were prepared by two different methods. Before that the silicone rubber (SR) was mixed well with sufficient amount of ethanol in one method, and without ethanol in the other method. It was found that the binary and ternary blends specimens that prepared with ethanol was chosen as the best samples have the highest experimental results of impact strength and a good homogeneous dispersion of silicon rubber in the resins as compared with the blends samples that prepared (without ethanol), which were selected to evaluate the lower mixing ratio (LMR) of these blends. The blends with (LMR) were selected and they are going to be considered as a matrix for the nano composite material to be reinforced by Al with 1% wt, and Al2O3 with 1% wt nanoparticles to develop the properties of (LMR) blends. Impact test was carried out on the blends with (LMR) and their nanocomposites at different environmental conditions before and after immersion in water for 4 weeks. Also hardness (shore D) test was carried out on the blends with (LMR) and their nanocomposites. The best results of this study befor imarsion in water were achieved with the nanocomposite material consisting of (LMR) binary blend reinforced with Al and (LMR) binary blend reinforced with Al2O3 nanoparticles. The results showed that after immersion period of 4 weeks, a decrease in the values of impact strength was observed for the samples of (LMR) binary and ternary blends without reinforcement. It also can be noted that impact strength was increased for the binary blends reinforcement with Al and Al2O3 nano particles after 4 weeks of immersion in water. Whereas it can be seen that ternary blends reinforcement with Al and Al2O3 nano particles would not achieve similar enhanced in impact strength as that of binary blends reinforcement with Al and Al2O3 nano particles after immersion in water.

Characterization and Properties of Polyurea Elastomer Used as Blast Mitigation Agent

The blast that caused from terrorist activities, explosion and weapons effect on not only the human life, but also the architectural structure. The development of materials used to protect them is needed. Polyurea is a one type of elastomer that derive from the reaction product of an isocyanate component and a synthetic resin blend component through step-growth polymerization. It is revealed that polyurea is a new entrant in the field of elastomer has received enormous attention in view of its excellent blast mitigation properties and ballistic protection. In this work, the microstructure and elemental composition of polyurea samples are studied using scanning electron microscope coupled with energy dispersive X-ray spectrometer (SEM-EDS). The main composition consisted of carbon, oxygen and silica approximately 63-75, 17-29, and 0.15-1.69 wt%, respectively. Sulfur and chlorine present as the chain extender. Titanium is added to modify its structure. Other elements present as the additives, fillers and pigments. Atomic force microscopy (AFM) is conducted to confirm nano-scale composition. Dynamic mechanical, thermal and tensile properties are also studied. It is shown that the modulus and loss factor increase as the increasing of the frequency and temperature. The elongation capacity is greater than 100%. Infrared spectroscopy based on synchrotron radiation (SR IR) shows the various constituents of the composition in the form of the functional groups along with the wave number.

Self-Healing and Mechanical Properties of Thermoplastic Polyurethane/Eugenol-Based Phenoxy Resin Blends via Exchange Reactions.

The possibility of exchange reactions and thermal self-healing in blends of thermoplastic polyurethane (TPU) and phenoxy resin was investigated herein. The analyses were based on characterization obtained via differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), dynamic mechanical analysis (DMA), and tensile test. A new phenoxy resin was synthesized from eugenol, and blends with different types of TPU were prepared to investigate the exchange reaction, thermal self-healing, and mechanical properties. The influence of phenoxy resin content on the mechanical behavior and healing efficiency was studied. Improvement of storage modulus owing to the increase of phenoxy resin content was observed. Results suggest that the exchange reaction between phenoxy- and ester-type TPU occurred during thermal treatment. However, little exchange occurred between phenoxy resin and ether-type TPU. Specifically, only ester-type TPU exhibited a significant exchange reaction in the phenoxy resin blend. Furthermore, in the presence of a catalyst (e.g., zinc acetate), the exchange reaction readily occurred, and the healing efficiency improved by the addition of the catalyst and increase in the phenoxy content.

Pine Resin Derivatives as Sustainable Additives to Improve the Mechanical and Thermal Properties of Injected Moulded Thermoplastic Starch

Fully bio-based materials based on thermoplastic starch (TPS) were developed starting from corn starch plasticized with glycerol. The obtained TPS was further blended with five pine resin derivatives: gum rosin (GR), disproportionated gum rosin (dehydroabietic acid, RD), maleic anhydride modified gum rosin (CM), pentaerythritol ester of gum rosin (LF), and glycerol ester of gum rosin (UG). The TPS–resin blend formulations were processed by melt extrusion and further by injection moulding to simulate the industrial conditions. The obtained materials were characterized in terms of mechanical, thermal and structural properties. The results showed that all gum rosin-based additives were able to improve the thermal stability of TPS, increasing the degradation onset temperature. The carbonyl groups of gum rosin derivatives were able to interact with the hydroxyl groups of starch and glycerol by means of hydrogen bond interactions producing a significant increase of the glass transition temperature with a consequent stiffening effect, which in turn improve the overall mechanical performance of the TPS-resin injected moulded blends. The developed TPS–resin blends are of interest for rigid packaging applications.

Epoxy polymers modified with polyetherimide. Part I: rheological and thermomechanical characteristics

Using the methods of viscometry, SEM, DMA the effect of polyetherimide (PEI) on the properties of ED-20 epoxy oligomer during and after curing was studied. It was shown that the introduction of the modifier significantly affects the kinetics of curing process and the structure of epoxy–polyetherimide matrices. The introduction of PEI reduces the curing time of epoxy resin blends. With increasing temperature, the curing time, working life and gel time of all compositions are reduced by an order. In homogeneous epoxy/PEI compositions, phase separation occurs during curing. It was found that with an increase in the PEI concentration to 25 parts by mass, the matrix-dispersion type of structure with PEI-rich particles and epoxy-rich continuous phase changes to a complex bicontinuous structure. The Young modulus of the cured compositions differs by no more than 15%, and the glass transition temperature (Tg) of the matrix with the addition of PEI increases.

Mechanical Properties of Graphite Filled Unsaturated Polyester and Unsaturated Polyester/Palm Oil Blend Resin

This research aim to investigate the effect of graphite loadings in unsaturated polyester (UPE) / acrylated epoxidized palm oil (AEPO) blend resin. The modification of epoxidized palm oil (EPO) to AEPO was carried out using acrylation process and further blended with synthetic UPE resin. Graphite powder was added at 0.03, 0.05 and 0.1 phr into the UPE/AEPO blend resin and cured in an oven at 100 °C and 160 °C. FTIR spectrums showed the disappearance of oxirane ring and existence of carbon double bond indicating successful of AEPO synthesis process. Tensile and Izod impact test revealed that, graphite showed different effects to neat UPE and UPE/AEPO blend resin. In neat UPE, graphite significantly improved the stiffness properties at 0.1 phr additions. However in UPE/AEPO blend resin, the toughness properties were improved with increased graphite loadings.

Comparison of different surface modifications on mechanical properties of HNTs incorporated CFRP for fine particle accumulation

This paper presents an investigation into the effect of particle accumulation on an amorphous halloysite nanotube (A-HNT)/Carbon fiber reinforced plastic (CFRP) laminate, fabricated through Vacuum-assisted Resin Transfer Molding (VaRTM). Resin blending and Electrophoretic deposition (EPD) methods were impeded to incorporate the A-HNTs. Bending, short beam shear (SBS), and end-notched flexure (ENF) tests were individually conducted on three sections, which were divided from an integral CFRP laminate. The anchoring effect of the carbon fibers and the scouring effect of the resin flow together lead to the different A-HNT accumulation patterns in both incorporation methods, and thus caused the observed distinctions in the properties of each separated section. Extensively incorporated A-HNTs showed a tendency to aggregate, resulting in the degradation of the material’s properties.

Enhanced flame retardancy of unsaturated polyester resin composites containing ammonium polyphosphate and metal oxides

AbstractThree metal oxides (MOs) (Fe2O3, Sb2O3, Al2O3) were incorporated into blends of unsaturated polyester resin (UPR)/ammonium polyphosphate (APP) composites with the aim of studying and comparing their synergistic effect on flame retardancy with APP. The UPR‐APP/MOs composites were prepared, then the thermal stability and flame‐retardant properties of the UPR composites were evaluated by thermogravimetric analysis (TGA), limiting oxygen index (LOI), vertical burning test (UL‐94), and cone calorimetry test (CCT). Besides, residues after CCT were characterized by scanning electron microscopy and laser Raman spectroscopy. The LOI values of the UPR composites with 0.5 wt% MOs increased to around 40%. However, the CCT results indicated that the incorporation of Sb2O3 brought an increase in the total heat release. Moreover, these three MOs had different effects on the process of thermal degradation of UPR composites from the TGA results. Based on the above results, Al2O3 provided a best promotion on flame retardancy among three MOs.

Preparation and properties of a novel fluorinated epoxy resin/DGEBA blend for application in electronic materials

A novel epoxy monomer 4-trifluoromethyl phenylhydroquinone epoxy resin (4-TFMEP) was synthesized via a multistep procedure including the Meerwein arylation reaction and followed by nucleophilic reaction. The chemical structure of 4-TFMEP was confirmed by proton nuclear magnetic resonance and Fourier-transform infrared spectrum. Then a mixed system (DGEBA/4-TFMEP x%) composed of diglycidyl ether of bisphenol A (DGEBA) and 4-TFMEP was prepared by a melting method without any solvent. After curing, the properties of this series of mixed epoxy resins were measured and compared with the neat DGEBA. As a result, the blend resins exhibited good thermal stability, excellent hydrophobic and low dielectric properties with 4-TFMEP content increasing. Furthermore, the material of DGEBA/4-TFMEP 40% achieves higher glass transition temperature of 104°C and char yield 33% than DGEBA (char yield = 22%) possessed. In the contact angle testing, DGEBA/4-TFMEP 40% shows 127.2° satisfied the standard of hydrophobic material. In addition, by the test of dielectric properties, DGEBA/4-TFMEP x% materials show lower than DGEBA/boron trifluoride ethylamine (BF3MEA) material, because of the introduced side group of fluorine content into the material improves the electronegativity of epoxy material and reduced the polarizability of molecules efficient. Herein, we believe the novel mixed epoxy system (DGEBA/4-TFMEP x%) has a potential application in electronic industries.