Effects of cationic starch in the presence of cellulose nanofibrils on structural, optical and strength properties of paper from soda bagasse pulp

Different strategies aimed at reducing the negative impact of fillers on paper strength have been the objective of many studies during the past few decades. Some new strategies have even been patented or commercialized, yet a complete study on the behavior of the filler flocs and their effect on retention, drainage, and formation has not been found in literature. This type of research on fillers is often limited by difficulties in simulating high levels of shear at laboratory scale similar to those at mill scale. To address this challenge, a combination of techniques was used to compare preflocculation (i.e., filler is flocculated before addition to the pulp) with coflocculation strategies (i.e., filler is mixed with a binder and flocculated before addition to the pulp). The effect on filler and fiber flocs size was studied in a pilot flow loop using focal beam reflectance measurement (FBRM) and image analysis. Flocs obtained with cationic polyacrylamide (CPAM) and bentonite were shown to have similar shear resistance with both strategies, whereas cationic starch (CS) was clearly more advantageous when coflocculation strategy was used. The effect of flocculation strategy on drainage rate, STFI formation, ash retention, and standard strength properties was measured. Coflocculation of filler with CPAM plus bentonite or CS showed promising results and produced sheets with high strength but had a negative impact on wire dewatering, opening a door for further optimization.

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Strong paper from spruce CTMP – Part II: Effect of pressing at nip press temperatures above the lignin softening temperature

Nordic Pulp & Paper Research Journal ◽

10.1515/npprj-2018-3009 ◽

2018 ◽

Vol 33 (1) ◽

pp. 142-149 ◽

Cited By ~ 1

Author(s):

Sven Norgren ◽

Gunilla Pettersson ◽

Hans Höglund

Keyword(s):

Compression Strength ◽

Kraft Pulp ◽

Softening Temperature ◽

Strength Properties ◽

Kraft Pulps ◽

Cationic Starch ◽

Tensile Index ◽

Very High

Abstract The main objective of the current study was to demonstrate that it is possible to enhance strength properties of sheets from spruce HT-CTMP and CTMP furnishes up to the same level as is common on sheets from softwood kraft pulps by changing conditions in papermaking. To achieve that, sheets of spruce HT-CTMP and CTMP were consolidated at densities close to that of the reference bleach kraft pulp by pressing at press nip temperatures well above the tack and softening temperatures of lignin. On sheets from spruce CTMP (CSF 420 ml), where the fibers were surface treated with cationic starch, it was possible to reach tensile index at the same level as on sheets from the untreated reference kraft pulp. The compression strength (SCT) of CTMP and HT-CTMP sheets, which were achieved at the highest press nip temperature (200 °C) in the study, was equal to or higher than that of the reference kraft pulp sheets. The results show that there is a great yet unexploited potential in papermaking from spruce HT-CTMP and CTMP furnishes, which could be utilized in manufacturing of products where very high requirements upon strength is demanded.

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Effect of lignin on the thermal stability of cellulose nanofibrils produced from bagasse pulp

Cellulose ◽

10.1007/s10570-019-02657-w ◽

2019 ◽

Vol 26 (13-14) ◽

pp. 7823-7835 ◽

Cited By ~ 19

Author(s):

Ni Zhang ◽

Peng Tao ◽

Yanxv Lu ◽

Shuangxi Nie

Keyword(s):

Thermal Stability ◽

Cellulose Nanofibrils ◽

Thermal Stability Of ◽

Bagasse Pulp

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Use of Oxalic-Acid-Modified Stellerite for Improving the Filter Capability of PM2.5 of Paper Composed of Bamboo Residues

International Journal of Polymer Science ◽

10.1155/2016/2198506 ◽

2016 ◽

Vol 2016 ◽

pp. 1-7

Author(s):

Hua Chen ◽

Jian Lou ◽

Fei Yang ◽

Jia-nan Zhou ◽

Yan Zhang ◽

...

Keyword(s):

Oxalic Acid ◽

Pore Formation ◽

Strength Properties ◽

Filtration Efficiency ◽

Kraft Pulping ◽

Paper Strength ◽

Cationic Starch ◽

Promising Technique ◽

Cooking Temperature ◽

Experimental Parameters

In this study, pulping conditions for kraft pulping of bamboo residues were investigated, predominantly focusing on cooking temperature and time during pulping. Oxalic acid and cationic starch were used for the modification of natural stellerite, and the use of modified stellerite for preparing filter paper for PM2.5 filtration was investigated. The optimal pulping technology of bamboo residues was established based on the following experimental parameters: liquor ratio of 1 : 5.5, cooking temperature of 160°C, and a holding time of 2 h. Modification by oxalic acid resulted in the promotion of pore formation at the stellerite surfaces and induced the microscopic changes. Nevertheless, paper strength remained practically unchanged after the addition of fillers, indicating that the cationic starch preblend method is a promising technique for papermaking because it enhances the strength properties of paper. With the variation in the addition of modified stellerite from 3 to 15%, while simultaneously maintaining the basis weight constant at 60 gm−2, the filtration efficiency of paper sheets first increased and then decreased later; thus the optimum stellerite content was found to be 9%. Filtration efficiency was suggested to be affected by gas flowing velocity.

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Effects of cationic starch addition and pulp beating on strength properties of softwood kraft pulp

Starch - Stärke ◽

10.1002/star.201300247 ◽

2014 ◽

Vol 66 (7-8) ◽

pp. 655-659 ◽

Cited By ~ 5

Author(s):

Sezgin Koray Gulsoy

Keyword(s):

Kraft Pulp ◽

Strength Properties ◽

Cationic Starch ◽

Softwood Kraft Pulp

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New Diatomite Filler for Improvement of Paper Strength Properties

Revista de Chimie ◽

10.37358/rc.20.5.8160 ◽

2020 ◽

Vol 71 (5) ◽

pp. 479-490 ◽

Cited By ~ 1

Author(s):

Wei Shang ◽

Haoran Han ◽

Hunan Liang

Keyword(s):

Particle Size ◽

Strength Properties ◽

Filler Loading ◽

Sodium Hexametaphosphate ◽

Paper Strength ◽

Pulp Fibers ◽

Cationic Starch ◽

Coating Method ◽

Filler Retention ◽

Modified Diatomite

In this work, diatomite particles were modified to improve the bondability of diatomite particles with pulp fibers and filler retention via a complex of cationic starch-sodium hexametaphosphate coating method. The particle size, FTIR spectroscopy characteristic and morphology of the resulting modified diatomite were studied to confirm the successful modification. The SEM results illustrated that the surface of modified diatomite particles was covered by the complex coatings. The coating efficiency of the complex of cationic starch-sodium hexametaphosphate on diatomite surface was up to 98%. Compared with the handsheet filled unmodified diatomite, the handsheet filled with modified diatomite had higher strength properties and lower bulk. When cationic starch dosage was 7%, and filler dosage was 25% , the resulting tensile strength of filled modified diatomite handsheet was 22.1% higher than the handsheet filled unmodified diatomite. Furthermore, with the filler loading of 30%, compared with that of unmodified diatomite, filler retention of modified diatomite was increased by 20.4%. The larger particle size and higher zeta potential of modified diatomite were benefitial to increase retention of modified diatomite filler.

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Role of Cellulose Nanofibrils in Improving the Strength Properties of Papers: A Review

10.21203/rs.3.rs-729909/v1 ◽

2021 ◽

Author(s):

Thabisile Brightwell Jele ◽

Prabashni Lekha ◽

Bruce Sithole

Keyword(s):

Cellulose Nanofibrils ◽

High Strength ◽

Barrier Properties ◽

Strength Properties ◽

Biochemical Properties ◽

Factors Affecting ◽

Tear Index ◽

Different Types ◽

Breaking Length

Abstract The pursuit for sustainability in the papermaking industry calls for the elimination or reduction of synthetic additives and the exploration of renewable and biodegradable alternatives. Cellulose nanofibrils (CNFs), due to their inherent morphological and biochemical properties, are an excellent alternative to synthetic additives. These properties enable CNFs to improve the mechanical, functional and barrier properties of different types of paper. The nanosize diameter, micrometre length, semi-crystalline structure, high strength and modulus of CNFs has a direct influence on the mechanical properties of paper such as tensile index, burst index, Scott index, breaking length, tear index, Z-strength, E-modulus, strain at break, and tensile stiffness. This review details the role played by CNFs as an additive to improve strength properties of papers and the factors affecting the improvement in paper quality when CNFs are added as additives. The paper also includes techno-economic aspects of the process and identifies areas that need further research.

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