Statistical Study on Additives Used to Improve Mechanical Properties of Polypropylene

Polypropylene (PP) is a semi-crystalline polymer that is brittle under severe conditions. To meet industry needs, and to increase the applications of polypropylene, its mechanical properties should be improved. In this research, the mechanical properties of polypropylene, such as tensile strength at break, tensile strength at yield, % elongation, and Young’s modulus, were improved using two types of additives. Additives used were calcium carbonate master batch filler composed of 80% calcium carbonate and 20% polyethylene, and a mixture of linear low-density polyethylene (LLDPE)/low density polyethylene (LDPE). Results showed that both tensile strength at break, and tensile strength at yield, decrease with increasing the amount of both additives. Percentage elongation of PP increased using both additives. The modulus of elasticity of PP increases by increasing the amount of both additives, until a value of 20 wt%. Analysis of variance (ANOVA test) or (F-test) shows significant differences between the effect of different weights of LLDPE/LDPE mixture and calcium carbonate filler on the four mechanical properties of polypropylene studied at a level of 0.05. T-tests are applied to compare between the effect of both calcium carbonate master batch filler and the mixture LLDPE/LDPE on the four mechanical properties of polypropylene studied. T-tests show no significant differences between the effect of both calcium carbonate master batch filler and the mixture LLDPE/LDPE on all mechanical properties of polypropylene studied at a level of 0.05.

Novel calcium carbonate filler for cellulose industry

Precipitated calcium carbonate (PCC) filler is used in many industrial products like constructions, plastics, pharmaceutics, etc. In this study producing cationic precipitated calcium carbonate filler for paper industry was investigated. Hence, a cationic polyacrylamide and cationic corn starch have been incorporated into the PCC particles to produce a modified filler with cationic structure and improved hydrogen bonding ability with cellulose fibers. According to the FESEM and XRD results, cubic-like fillers with prominently calcite polymorph and a slight amount of aragonite were successfully produced from the industrial burnt lime using carbonation process. The presence of organic substances in the structure of the modified samples was confirmed by FT-IR analysis. Besides, based on the FESEM results, filler morphology and particle size could be affected by the polymer content. In conclusion, introducing cationic groups to mineral fillers could be considered as a possible strategy to overcome some detrimental effects of using mineral fillers in paper products.

Perbandingan Karakteristik Plastik Biodegradable dari Biji Durian menggunakan Filler Kalsium Silikat dan Kalsium Karbonat

Pada penelitian ini biji durian digunakan sebagai sumber pati dalam pembuatan plastik biodegradable. Penelitian ini bertujuan untuk mengetahui pengaruh jenis dan jumlah filler terhadap sifat biodegradable, sifat mekanik dan sifat water absorbtion pada plastik biodegradable berbasis pati biji buah durian. Plasticizer yang digunakan dalam penelitian ini adalah sorbitol 40%, sedangkan filler yang digunakan adalah Kalsium silikat (Ca2SiO4) dan Kalsium karbonat (CaCO3) dengan variable konsentrasi 2%, 4%, 6%, dan 8%. Dari hasil penelitian, diperoleh % yield dari pati biji buah durian sebesar 34,57%. Hasil dari plastik biodegradable terbaik dengan karakteristik transparan, tidak ada gelembung, lentur serta permukaan yang halus diperoleh pada variabel penambahan filler kalsium karbonat 4%. Hasil uji bio-degradasi paling mendekati standard ASTM D6400 diperoleh pada variabel kalsium karbonat 2%. Pada Uji water absorption hasil terbaik dicapai pada variabel kalsium silikat 8%. Uji tarik hasil terbaik diperoleh pada variabel kalsium silikat 6%.In this study, durian seeds were used as a source of starch in making biodegradable plastics. This study aims to determine the effect of the type and amount of filler on biodegradable properties, mechanical properties, and water absorption properties of biodegradable plastics based on durian fruit starch. The plasticizer used in this study was sorbitol 40%, while the filler used was Calcium silicate (Ca2SiO4) and Calcium carbonate (CaCO3) with variable concentrations of 2%, 4%, 6%, and 8%.. From the research results, the% yield of durian seed starch was 34.57%. The results of the best biodegradable plastic with the characteristics of transparent, no bubbles, flexible and smooth surface were obtained with the addition of 4% calcium carbonate filler variables. The bio-degradation test results closest to the ASTM D6400 standard were obtained in the 2% calcium carbonate variable. In the water absorption test, the best results were achieved at the 8% calcium silicate variable. The best tensile test results were obtained in the 6% calcium silicate variable.

Impact of Bimodal Particle Size Distribution Ratio of Functional Calcium Carbonate Filler on Thermal and Flowability Properties of Polyamide 12

In previous investigations, it was shown that the melting, as well as crystallization behavior of polyamide 12, could be manipulated by adjusting the particle size distribution of calcium carbonate as a functional filler. It was demonstrated that the melt properties of this compound show a significant dependency on the filler volume-based particle size. As finer and narrower the calcium carbonate particles in the polymer matrix become, the less influence the filler has on the melting properties, influencing the melt flow less significantly than the same surface amount of broad size distribution coarse calcium carbonate filler particles. However, due to increased nucleation, the crystallization behavior on cooling showed a markedly more rapid onset in the case of fine sub-micrometer filler particle size. To control further and optimize the thermal response properties of a filling compound for improved properties in additive manufacturing processing through selective laser sintering, the possibility to combine precisely defined particle size distributions has been studied, thereby combining the benefits of each particle size range within the chosen material size distribution contributes to the matrix. The melt flow at 190 °C, the melting speed, melting and crystallization point as well as crystallization time at 170 °C were analyzed. The thermal and flow properties of a polyamide 12 matrix can potentially be optimized with a combination of a precise amount of coarse and fine calcium carbonate filler. The improvements were exemplified using a twin-screw extruder for compounding, indicating the potential for optimizing functionally filled polymer in additive manufacturing.

Effect of calcium carbonate filler and alkali treatment on physical and elastic properties of jute mat reinforced polyester resin composites

Polyester resin-jute mat reinforced composites with different wt% of calcium carbonate (CaCO3) filler were fabricated using a simple cold press molding method. The effects of CaCO3 filler and alkali (NaOH) treatment on various physical and elastic properties were evaluated. Water absorption (WA) increases with the increase of soaking time and load. The maximum WA was observed for 5 wt% addition of CaCO3 and for more CaCO3, WA decreases. The ultimate tensile strength (UTS) and flexural strength (FS) decreases with the addition of CaCO3 for 0.5 wt% NaOH treated composites but for 5 wt% NaOH treated composites UTS and FS increases with the addition of CaCO3 filler. The optimum filler addition is about 5 wt% CaCO3. With the addition of CaCO3, tangent modulus increases for 0.5 wt% NaOH treated composites and for 5 wt% NaOH treated composites it increases up to a maximum value and then decreases. The effect of load on tensile and flexural properties is also discussed. Bangladesh Journal of Physics, 26(2), 61-68, December 2019

Response surface optimization and statistical analysis of composites made from calcium carbonate filler-added recycled polypropylene and rubberwood fiber

Mixture design method of experiments was used to determine the compositions of wood-plastic composite samples manufactured from recycled polypropylene (rPP), rubberwood flour (RWF), and calcium carbonate (CC). Factors were determined the mixture compositions rPP, RWF, CC, maleic anhydride-grafted polypropylene (MAPP), ultraviolet (UV) stabilizer, and lubricant (Lub) on properties of the samples, namely tension, compression, surface roughness, water absorption (WA), thickness swelling (TS), and thermogravimetric analysis (TGA). The specimens were produced by extrusion and compression molding methods. The analysis of variance and response surface methodology were employed for the analysis and optimization of the compositions. Optimal composition for overall response was 51.8 wt% rPP, 35.9 wt% RWF, 7.2 wt% CC, 3.9 wt% MAPP, 0.2 wt% UV stabilizer, and 1.0 wt% Lub with desirability score combining their output value of 0.757. The addition of CC content increased the mechanical properties but decreased the WA and TS. A high RWF content increased WA and TS with longer immersion times. The TGA of composites mainly depends on the chemical components of RWF and rPP types. The scanning electron microscope morphology in the composites with different amount of CC increased their densities due to good dispersion of CC as filler and good contact between the RWF reinforcement and rPP matrix.

The Effect of Calcium Carbonate Filler on Self-Compacting Concrete Using Different Aggregate Sizes

In this research work, the effect of Calcium Carbonate Filler was studied on the compressive strength and the workability of self-compacting Concrete (SCC) at different grades (M60, M65 and M70) and different coarse aggregate sizes (6.3mm, 10mm and 20mm). Calcium Carbonate Filler (Limestone powder) and Rice Husk Ash (RHA) were added in percentages of 2.5% and 5% to check its effect on the workability and strength properties of SCC and Normally Vibrated Concrete. Experimental investigations were carried out on SCC and normally vibrated concrete (NVC) samples of grade M60, M65 and M70 using different aggregate sizes of 6.3mm, 10mm and 20mm. The workability test results obtained showed values within specification. The compressive and Tensile strengths for SCC (with powder and 2.5% RHA) are higher than that with powder and 5% RHA and NVC. Generally, the use of Calcium Carbonate Filler improved the strength and densities for SCC design mix and decreased its workability. It is concluded that the use of SCC with designed Fillers ratio and RHA (≤5%) will improve the strength properties of SCC.