The use of hollow sphere pigments as strength additives in paper and paperboard coatings—Part 1: The predictive nature of packing models on coating properties

TAPPI Journal ◽  
2020 ◽  
Vol 19 (11) ◽  
pp. 585-593
Author(s):  
ETHAN GLOR ◽  
BRIAN EINSLA ◽  
JOHN ROPER ◽  
JIAN YANG ◽  
VALERIY GINZBURG

Hollow sphere pigments (HSPs) are widely used at low levels in coated paper to increase coating bulk and to provide gloss to the final sheet. However, HSPs also provide an ideal system through which one can examine the effect of pigment size and particle packing within a coating due to their unimodal and tunable particle sizes. The work presented in Part 1 and Part 2 of this study will discuss the use of blends of traditional inorganic pigments and HSPs in coating formulations across a variety of applications for improved coating strength. Part 1 of this study focuses on the theory of bimodal spherical packing and demonstrates the predictive nature of packing models on the properties of coating systems containing HSPs of two different sizes. This study also examines conditions where the model fails by examining the effect of particle size on coating strength in sytems like thermal paper basecoats where the non-HSP component has a broad particle size distribution, and how these surprising trends can be used to generate better-than-expected thermal printing performance in systems with low HSP/clay ratios. Part 2 of this study focuses on the incorporation of HSPs of different particle sizes into paperboard formulations to affect coating strength and opacity.

2013 ◽  
Vol 60 (1) ◽  
Author(s):  
Mohd Azizi Che Yunus ◽  
Manzurudin Hasan ◽  
Norasikin Othman ◽  
Siti Hamidah Mohd-Setapar ◽  
Liza Md.-Salleh ◽  
...  

Kajian ini bertujuan untuk mengkaji kesan saiz zarah ke atas pengekstrakan sebatian catechin daripada biji Areca catechu L. dengan menggunakan Pengekstrakan Pelarut Terpecut (PPT). Saiz zarah biji Areca catechu dipelbagaikan dari 75 μm sehingga 500 μm. Pengekstrakan telah dijalankan padaparameter tetap iaitu suhu (140oC), tekanan (1500 psi), masa (10 minit), isipadu semburan (60%) dan satu kitaran pengekstrakan, masing-masing. Hasil minyak peratusan yang lebih tinggi adalah 300 mg minyak / gram sampel (30.00% pati minyak) ditemui pada 125 μm. Walaubagaimanapun, kandungan catechin dalam pati minyak hanya 0.0375 mg catechin / gram sampel. Saiz zarah yang terbaik dalam julat uji kaji ini telah dikenal pasti pada 500 μm yang memberikan kandungan catechin yang tinggi iaitu 0.0515 mg catechin / gram sampel dari 247.5 mg minyak / gram sampel (24.75% pati minyak). Kata kunci: Saiz zarah; catechin; LC-MS-TOF; pengekstrakan pelarut terpecut The purpose of this work is to investigate the effects of particle size on the extraction of catechincompound from Areca catechu L. seeds by using Accelerated Solvent Extraction (ASE). The particle sizes of Areca catechu L. seeds are varied from 75 µm until 500 µm. The extraction is conducted at fixed parameters which are temperature (140oC), pressure (1500 psi), extraction time (10 minutes), flush volume (60%) and the static cycle is done for 1 extraction cycle respectively. Higher percentage oil yield of 300mg oil/gram of sample (30.00% oil yield) is found at 125 µm. However, the amount of catechin in oil yields is only 0.0375 mg of catechin/gram of sample. The best of particle size within the experimental range has been identified at 500 µm which gives a high content of catechin with 0.0515 mg Catechin/gram of sample from 247.5 mg oil/gram of sample (24.75% oil yield). Keywords: Particle size; catechin; LC-MS-TOF; accelerated solvent extraction


2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Carola Contreras ◽  
Fernanda Isquierdo ◽  
Pedro Pereira-Almao ◽  
Carlos E. Scott

More than half of the total world oil reserves are heavy oil, extra heavy oil, and bitumen; however their catalytic conversion to more valuable products is challenging. The use of submicronic particles or nanoparticles of catalysts suspended in the feedstock may be a viable alternative to the conversion of heavy oils at refinery level or downhole (in situ upgrading). In the present work, molybdenum sulfide (MoS2) particles with varying diameters (10000–10 nm) were prepared using polyvinylpyrrolidone as capping agent. The prepared particles were characterized by DLS, TEM, XRD, and XPS and tested in the hydrodesulfurization (HDS) of a vacuum gas oil (VGO). A correlation between particle size and activity is presented. It was found that particles with diameters around 13 nm show double the HDS activity compared with the material with micrometric particle sizes (diameter ≈ 10,000 nm).


2005 ◽  
Vol 23 (6) ◽  
pp. 437-453 ◽  
Author(s):  
M.S. El-Geundi ◽  
T.E. Farrag ◽  
H.M. Abd El-Ghany

The equilibrium adsorption of a herbicide (pendimethalin) onto natural clay from aqueous solutions was studied experimentally using different system variables. The influence of such variables, such as particle size (dp), pH and temperature, on the adsorption capacity was studied. Equilibrium modelling was carried out using the Langmuir, Freundlich and Redlich—Peterson models with the corresponding constants being calculated for the different system variables. The results indicate that the maximum adsorption capacity (qmax) at an acidic pH value (3.44) was approximately double that observed at an alkaline pH value (9.62). It was also found that the effect of particle size was significant and that the temperature plays an interesting role in the adsorption process. The enthalpy change (ΔH) for adsorption was evaluated as −29.36 kJ/mol. It is clear from the results of this study that the Freundlich model fitted the experimental adsorption data significantly better than the Langmuir or the Redlich—Peterson models.


Author(s):  
Jesus Djalma PÉCORA ◽  
Ricardo Gariba SILVA ◽  
Ricardo Novak SAVIOLI ◽  
Luis Pascoal VANSAN

A study was conducted on the hardening time of three Grossman's cements with different powder particle sizes (60, 100 and 150 mesh) using Specification n. 57 of the AMERICAN DENTAL ASSOCIATION1 (1983). The cement obtained from mesh 150 particles showed the longest hardening time (22 minutes), which was different when compared to mesh 60 (17 minutes) and 100 (17 minutes) particles.


2008 ◽  
Vol 31 (2) ◽  
pp. 1-13
Author(s):  
S.V. Manyele ◽  
I.F. Kahemel

An investigation of the effect of particle size on the performance of vegetable oil recovery by solvent extraction is reported. Experiments were conducted using soxhlet extractor, groundnuts and n-hexane. Samples were grouped into mean particle sizes of 0.25, 0.75, 1.3, 3.3, and 7.5 mm using standard sieves. The effect of particle size was studied for extraction time intervals of 1, 2, 3, 4, 5 and 8 hours. The oil yield, oil recovered per kg solvent used, kg solvent lost per unit time, and the rate of extraction (kg oil recovered per hour) decreased with increasing particle size. Meanwhile, the percent of solvent recovered, the ratio of oilrecovered to the total volatile matter driven off and the kg solvent lost per kg oil recovered, increased with increasing particle size. Based on the normalization of averaged extraction-parameters, a mean particle size of 3.3 mm was observed to be the optimum size.


2020 ◽  
pp. 1-19
Author(s):  
Qiuchen Wang ◽  
Qiyu Huang ◽  
Xu Sun ◽  
Jun Zhang ◽  
Soroor Karimi ◽  
...  

Abstract During petroleum production, sand particles can be entrained with the transported carrier fluid despite of any sand exclusion process and erode the inner walls of pipelines. This erosion process may even cause pipe leakage and oil spill. Therefore, investigate the regularities of erosion damage changing with particle sizes and predict erosion behavior under different sizes particles are important to pipeline safety. In this study, slurry erosion experiments are conducted using quartz particles with similar shapes and different sizes ranging from 25 micrometers to 600 micrometers to investigate the effect of particle size on erosion profiles and provide the database for evaluating models. Computational Fluid Dynamics (CFD) is used to simulate the fluid flow and track particles to obtain impact information. Erosion equations then connect the particles' impact information with erosion rate. Finally, the available mechanistic and empirical equations erosion models are evaluated by comparing predicted erosion profile with experimental data. It was found that the local maximum erosion damage increases with particle sizes although the total erosion ratio is not increasing. These changes of erosion profiles can be predicted with acceptable accuracy by available empirical erosion models when particle sizes are no less than 75 micrometers.


2019 ◽  
Vol 37 (No. 2) ◽  
pp. 120-127
Author(s):  
Hüseyin Boz

The effect of particle size of flour and sugar on the physical, sensorial and textural properties of cookie dough and cookie was investigated. According to the obtained data, both the sugar particle size and the flour particle size in cookie dough affected the hardness, adhesiveness, cohesiveness and springiness of the cookie doughs and this effect was statistically at a significant level (P < 0.01). The energy and force required for the dough extrusion dropped due to the reduction in the particle size of flour, while the reduction in the particle of sugar had the opposite effect. As the sugar and flour particle sizes decreased, the colour of the cookies became darker and the L colour values decreased. While the hardness values of the cookie samples increased with the decrease in the particle size of sugar, it decreased with the decrease in the particle size of flour. It was observed that sugar and flour particle size significantly affect cookie quality in cookie production. The formulation containing sugar and flour fractions below 150 µm has received the highest score in all sensory parameters.


2010 ◽  
Vol 7 (2) ◽  
pp. 57
Author(s):  
Jamaludin Kasim ◽  
Shaikh Abdul Karim Yamani ◽  
Ahmad Firdaus Mat Hedzir ◽  
Ahmad Syafiq Badrul Hisham ◽  
Mohd Arif Fikri Mohamad Adnan

An experimental investigation was performed to evaluate the properties of cement-bonded particleboard made from Sesendok wood. The target board density was set at a standard 1200 kg m·3• The effect of particle size, wood to cement ratio and the addition of sodium silicate and aluminium silicate on the wood cement board properties has been evaluated. A change of particle size from 1.0 mm to 2.0 mm has a significant effect on the mechanical properties, however the physical properties deteriorate. Increasing the wood to cement ratio from 1:2.25 to 1:3 decreases the modulus of rupture (MOR) by 11% and the addition of sodium silicate improves values farther by about 28% compared to the addition of aluminium silicate. The modulus of elasticity (MOE) in general increases with increasing cement content, but is not significantly affected by the addition of sodium silicate or aluminium silicate, although the addition of their mixture (sodium silicate and aluminium silicate) consistently yields greater MOE values. Water absorption and thickness swelling is significantly affected by the inclusion of additives and better values are attained using higher wood to cement ratios.


2008 ◽  
Vol 47-50 ◽  
pp. 916-919 ◽  
Author(s):  
Chaiy Rungsiyakull ◽  
Qing Li ◽  
Wei Li ◽  
Richard Appleyard ◽  
Michael Swain

This paper aims at providing a preliminary understanding in biomechanics with respect to the effect of the particle size of Fully Porous-Coated (FPC) dental implant on osseointegration. 2D multiscale finite element models are created for a typical dental implantation setting. Under a certain mastication force (<200N), a global response is first obtained from a macro-scale model (without considering morphological details on the coated surface), and then it is transferred to micro-scale models (with coated surface morphology details in three different particle sizes). An equivalent strain is analyzed to investigate the effect of particle size of the FPC materials on osseointegration and initiation of bone remodelling. The result reveals that increasing particle sizes has a significant effect on biomechanical and bone remodelling responses.


2019 ◽  
Vol 28 (6) ◽  
pp. 410-420 ◽  
Author(s):  
R Vinayagamoorthy

The present research has been made to investigate the characteristics of a new composite material made up of limestone as particle reinforcement. New composites are made by taking limestone particles in five different sizes and jute as woven reinforcement in polypropylene matrix. Mechanical characteristics of the composites that include strengths against tension, compression, flexural, impact and hardness are evaluated and a comparative investigation is made among the composites. The effect of particle size on the properties is analysed and found that the composite with medium particle size bears the highest strength in all aspects. In addition, microscopic image analysis is carried out to investigate the distribution of particles, bonding capacity and other morphologies. The results showed that limestone will be apt particle reinforcement and its presence enhances all the characteristics of the composite.


Sign in / Sign up

Export Citation Format

Share Document