Role of calcium carbonate morphology on thermal and mechanical properties of HDPE

et al. 2021

BioRes

The purpose of the study was to inspect the mechanical and thermal properties of four kinds of core-shell structured bamboo-plastic composites (BPCs). The materials that were used for the fabrication of the BPCs were high density polyethylene (HDPE), bamboo pulp fibers (BPF)/HDPE, nano-CaCO3/HDPE, and white mud (WM)/HDPE. As verified by flexural properties and impact properties, the dispersion of the BPF, nano-CaCO3, and WM in the HDPE matrix was inhomogeneous. The fracture surface of the scanning electron microscope (SEM) images showed that some aggregates existed in the HDPE. Additionally, X-ray diffraction (XRD) was used to corroborate the results. The thermogravimetric analysis (TGA) showed that the samples with the WM/HDPE shell has little effect on the thermal stability. However, the apparent activation energy (Ea) values of the nano-CaCO3/HDPE shell were higher than those of the other samples, which indicated better thermal stability. The thermal stability had no remarkable changes with the addition of the WM and BPF. The differential scanning calorimeter (DSC) curves revealed that the relative crystallinity of the BPCs increased with the addition fillers, which suggested that the fillers can act as nucleating agents.

Section: Characterization Of the Samplessupporting

confidence: 86%

Effect of different shell materials on the mechanical and thermal properties of core-shell structured bamboo-plastic composites

et al. 2021

BioRes

“…Therefore, the crystallization of HDPE molecules could occur at a higher temperature. Some similar results have been reported by Shi et al (2013) and Colom et al (2000). However the crystallinity of the composites decreased initially, and then they increased.…”

Section: Thermal Properties Thermogravimetrysupporting

confidence: 80%

“…As the WM content increased, the Tonset of composites increased from 100.58 °C to 107.57 °C. A possible explanation for this was that a small amount of WM acted as a nucleating agent during the crystallization of HDPE, such that the activation energy of HDPE was reduced (Shi et al 2013). The crystallinity of BPCs decreased with lower WM content (14 wt%), indicating the presence of a small amount of WM that adsorbed in the cracks in the BRFs.…”

Section: Thermal Properties Thermogravimetrymentioning

confidence: 99%

“…The poor compatibility between the WM and HDPE led to unstable interfacial adhesions, such that cracks tended to grow and spread. When the impact force hit the BPCs, the BPCs absorbed less and less impact energy as the WM increased (Shi et al 2013). Besides, as the WM increased in the composites, correspondingly, the amount of flexible and tougher HDPE was reduced (Wang and Yang 2009), which did not absorb enough energy.…”

Section: Impact Strengthmentioning

confidence: 99%

See 1 more Smart Citation

Effect of White Mud as a Second Filler on the Mechanical and Thermal Properties of Bamboo Residue Fiber/Polyethylene Composites

et al. 2015

BioResources

The purpose of this study was to investigate the effect of white mud (WM) on mechanical and thermal properties of bamboo plastic composites (BPCs). Bamboo residue fibers (BRFs) and WM were added as the reinforcement, and high-density polyethylene (HDPE) served as the matrix. The lubricating agent and coupling agent were polyethylene wax and maleated polyethylene (MAPE), respectively. The mixture was used to manufacture BPCs using a twin-screw extruder. The crystal structure and thermal properties of BPCs were investigated by X-ray diffraction (XRD), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The results showed that the particle size of the WM was 700 nm to 50 μm, which are made mainly of calcium carbonate. BPCs with WM significantly increased the flexural and tensile properties, but the impact strength decreased because of the presence of WM. The flexural and tensile strength of composites with 18 wt% BPF were increased by 36.81% and 6.26%, respectively, while the flexural and tensile modulus were increased by 164.29% and 64.33%, respectively. XRD demonstrated the WM had little effect on the crystal structure of BPCs. Compared to BPCs without WM, the T5% of composites with 22 wt% WM decreased by 27.9 °C. As the WM content increased, the crystallinity of the BPCs decreased initially, then increased with increasing WM content.

“…The impact strength of WM-filled BPCs decreased significantly, due to the fact that the micro/nano WM filling effect was poor or hard to fill in tiny gaps of BRF and HDPE, yet they are profoundly incompatible and there were more local stress concentrations generated in the BPCs, so that cracks tend to grow and spread. This can be seen from SEM images of BPCs (Figure 6); it was found that no visual effectively filling was evident in the BPCs [31]. Besides, the compatibility between the WM and HDPE becomes poor with the increasing amount of WM, which led to unstable interfacial adhesions [32].…”

Section: Resultsmentioning

confidence: 99%

Characterization and Research on Mechanical Properties of Bamboo Plastic Composites

et al. 2018

Polymers

The focus of this study was to observe the mechanical properties of bamboo plastic composites (BPCs) with bamboo pulp fiber (BPF) or white mud (WM). The essential work of fracture (EWF) methodology was used to characterize the impact toughness of BPCs. The results revealed an increase in flexural, tensile and impact properties, when adding the BPF in the BPCs. While the flexural properties of WM-reinforced BPCs revealed increasing, there was a decrease in tensile and impact strength. In an impact strength analysis study, BPF-filled BPCs showed excellent impact property over WM-filled BPCs; scanning electron microscopy (SEM) helps to explain impact fracture behavior of BPCs. EWF analysis of impact results showed that the specific essential work of fracture (we) increased significantly with the amount of BPF used in BPCs but decreased with the increase of WM in the BPCs. There was similar variation for the non-essential plastic work (βwp) of BPCs. This result indicates that the fracture initiation and fracture propagation of BPCs are different.