The effect of different polysaccharides on the development of paper strength during drying

We studied three process modifications to investigate their effects on the property and yield recovery capabilities of kraft pulping integrated with hemicellulose pre-extraction of southern pine. Loblolly pine chips were pre-extracted with hot water until the sugar extraction yield reached the targeted value of 10% and then subjected to conventional and modified kraft pulping. Modification included polysulfide pretreatment; polysulfide-sodium borohydride dual pretreatment, and polysulfide followed by polysulfide-sodium borohydride dual pretreatment two-stage pretreatments prior to kraft pulping. In the first modification, about 5% of the lost pulp yield (total 7%) caused by hemicellulose pre-extraction could be recovered with 15%-20% polysulfide pretreatment. Complete recovery (7%) was achieved with simultaneous pretreatment using 15% polysulfide and 0.5% sodium borohydride with 0.1% anthraquinone in polysulfide-sodium borohydride dual pretreatment. Two-stage pretreatment using recycled 15% polysulfide followed by simultaneous treatment of 6% polysulfide and 0.4%–0.5% sodium borohydride with 0.1% anthraquinone also achieved 100% yield recovery. Continuous recycling of 15% polysulfide employed in the two-stage process modification maintained its yield protection efficiency in a repeated recycling cycle. No significant changes in paper strength were found in handsheets prepared from the three process modifications, except for a minor reduction in tear strength.

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Complex formation of modified chitosan and carboxymethyl cellulose and its effect on paper properties

TAPPI Journal ◽

10.32964/tj8.6.29 ◽

2009 ◽

Vol 8 (6) ◽

pp. 29-35 ◽

Cited By ~ 11

Author(s):

PEDRAM FATEHI ◽

LIYING QIAN ◽

RATTANA KITITERAKUN ◽

THIRASAK RIRKSOMBOON ◽

HUINING XIAO

Keyword(s):

Carboxymethyl Cellulose ◽

Polymer System ◽

Layer By Layer ◽

Paper Strength ◽

Anionic Polymer ◽

Paper Properties ◽

Modified Chitosan ◽

Layer By Layer Assembly ◽

Polyelectrolyte Titration ◽

Layer Assembly

The application of an oppositely charged dual polymer system is a promising approach to enhance paper strength. In this work, modified chitosan (MCN), a cationic polymer, and carboxymethyl cellulose (CMC), an anionic polymer, were used sequentially to improve paper strength. The adsorption of MCN on cellulose fibers was analyzed via polyelectrolyte titration. The formation of MCN/CMC complex in water and the deposition of this complex on silicon wafers were investigated by means of atomic force microscope and quasi-elastic light scattering techniques. The results showed that paper strength was enhanced slightly with a layer-by-layer assembly of the polymers. However, if the washing stage, which was required for layer-by-layer assembly, was eliminated, the MCN/CMC complex was deposited on fibers more efficiently, and the paper strength was improved more significantly. The significant improvement was attributed to the extra development of fiber bonding, confirmed further by scanning electron microscope observation of the bonding area of fibers treated with or without washing. However, the brightness of papers was somewhat decreased by the deposition of the complex on fibers. Higher paper strength also was achieved using rapid drying rather than air drying.

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A novel predictive method for filler coflocculation with cellulose microfibrils

TAPPI Journal ◽

10.32964/tj18.11.653 ◽

2019 ◽

Vol 18 (11) ◽

pp. 653-664

Author(s):

IGNACIO DE SAN PIO ◽

KLAS G. JOHANSSON ◽

PAUL KROCHAK

Keyword(s):

Negative Impact ◽

High Strength ◽

Strength Properties ◽

Cellulose Microfibrils ◽

Paper Strength ◽

Flow Loop ◽

Cationic Starch ◽

Reflectance Measurement ◽

Drainage Rate ◽

Complete Study

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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Improvement of Paper Strength by Cellulase Enzyme

JAPAN TAPPI JOURNAL ◽

10.2524/jtappij.73.550 ◽

2019 ◽

Vol 73 (6) ◽

pp. 550-553

Author(s):

Kota Yoshimura ◽

Masanobu Hatano

Keyword(s):

Paper Strength ◽

Cellulase Enzyme

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Further understanding the influence of fiber surface and internal charges on the interfiber bonding capability and resulting paper strength

Cellulose ◽

10.1007/s10570-017-1300-3 ◽

2017 ◽

Vol 24 (7) ◽

pp. 2977-2986 ◽

Cited By ~ 2

Author(s):

Chengke Zhao ◽

Hongjie Zhang ◽

Zhiqiang Li ◽

Fengshan Zhang ◽

Xiaoliang Li

Keyword(s):

Fiber Surface ◽

Paper Strength

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Quantification of vegetable oil in recycled paper

TAPPI Journal ◽

10.32964/tj19.9.473 ◽

2020 ◽

Vol 19 (9) ◽

pp. 473-477

Author(s):

YAO NTIFAFA ◽

MARIA SZAJDA-LAM ◽

ASHOK GHOSH ◽

PETER W. HART

Keyword(s):

Soybean Oil ◽

Vegetable Oil ◽

Oil Content ◽

Strength Loss ◽

Gas Chromatography Mass Spectrometry ◽

Paper Strength ◽

High Concentration ◽

Recycled Paper ◽

Pyrolysis Gas ◽

Cooking Process

Vegetable soybean oil is commonly used in cooking foods that are packaged in takeaway paper-board containers. Vegetable oil is hydrophobic, and in sufficiently high concentration, could interfere with interfiber bonding and result in paper strength loss. In order to quantify the effect of oil on the resulting paperboard strength, it is necessary to quantify the oil content in paper. A lab method was evaluated to determine the soybean oil content in paper. Handsheets were made with pulps previously treated with different proportions of vegetable oil. Pyrolysis gas chromatography-mass spectrometry (pyGCMS) was used to quantify the amount of oil left in the handsheets. The results revealed a strong correlation between the amount of oil applied to the initial pulp and the amount of oil left in the handsheets. In addition, the effect of vegetable oils on paper strength may be affected by the cooking process. Vegetable oil is known to degrade over time in the presence of oxygen, light, and temperature. The vegetable oil was put in an oven to imitate the oil lifecycle during a typical pizza cooking process. The cooked oil was then left at room temperature and not protected from air (oxygen) or from normal daylight. The heated, then cooled, oil was stored over a period of 13 weeks. During this time, samples of the aged oil were tested as part of a time-based degradation study of the cooked and cooled oil.

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Strengthening effects of carboxymethylated hemicellulosic fractions on paper strength

Industrial Crops and Products ◽

10.1016/j.indcrop.2018.09.014 ◽

2018 ◽

Vol 125 ◽

pp. 360-369 ◽

Cited By ~ 1

Author(s):

Yushuang Zhao ◽

Shuangshuang Jing ◽

Xiaoting Zhang ◽

Zehong Chen ◽

Hao Zhuo ◽

...

Keyword(s):

Paper Strength

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Aplikasi Lakase pada Proses Refining Pulp

JURNAL SELULOSA ◽

10.25269/jsel.v9i02.274 ◽

2019 ◽

Vol 9 (02) ◽

pp. 65

Author(s):

Hendro Risdianto ◽

Sonny Kurnia Wirawan ◽

Susi Sugesty

Keyword(s):

Reaction Rate ◽

Refining Process ◽

Enzyme Treatment ◽

Paper Strength ◽

Tensile Index ◽

Tear Index ◽

Acacia Crassicarpa

Refining merupakan proses untuk memodifikasi serat dengan tujuan meningkatkan ikatan serat dan mengembangkan kekuatan kertas. Penelitian yang telah dilakukan meliputi penentuan kondisi refining dengan PFI Mill dan penentuan kondisi perlakuan awal lakase yang selanjutnya akan diterapkan pada proses biorefining. Jumlah putaran 2500 dari PFI mill merupakan jumlah yang optimum untuk menghasilkan kekuatan pulp Acacia crassicarpa. Sedangkan hasil penelitian kondisi optimum lakase menunjukkan bahwa lakase memiliki laju reaksi yang paling tinggi (0,0018 mM/s) pada suhu 50°C. Pada proses refining, freeness awal pulp adalah sekitar 550 mL CSF, dan ketika dikenakan perlakuan lakase turun menjadi 515 (LMS1) dan 520 (LMS2). Refining pulp tanpa perlakuan enzim menghasilkan indeks tarik, retak dan sobek berturut-turut adalah 6,4.10-2 kNm/g, 5,18 kPa.m2/g, dan 5,96 mN.m2/g. Indeks sobek tidak mengalami perubahan signifikan pada semua perlakuan. Perlakuan LMS1 meningkatkan indeks tarik menjadi 6,83 kNm/g dan indeks sobek menjadi 7,53 mN.m2/g. Indeks tarik dan sobek pada LMS2 menurun dibandingkan LMS1, namun masih lebih tinggi dibandingkan tanpa perlakuan. Dengan demikian perlakuan lakase pada proses refining dapat meningkatkan indeks tarik dan indeks sobek lembaran.Laccase Application in Pulp Refining Process AbstractRefining is a process to modify fibers with the aim of increasing fiber bonds and developing paper strength. The research that has been done includes determining the refining conditions with PFI Mill and determining the conditions of pretreatment of laccase which will then be applied to the biorefining process. The PFI mill revolutions of 2500 is the optimum to produce the strength of the Acacia crassicarpa pulp. Whereas the results of the study showed that optimum laccase conditions showed that laccase had the highest reaction rate (0.0018 mM/s) at 50oC. In the refining process, the initial freeness of the pulp is around 550 mL CSF, and when subjected to laccase treatment it drops to 515 (LMS1) and 520 (LMS2). Refining the pulp without enzyme treatment produced tensile, bursting and tearing indexes of 6.4.10-2 kNm/g, 5.18 kPa.m2/g, and 5.96 mN.m2/g, respectively. The tear index did not change significantly in all treatments. The LMS1 treatment increased the tensile index to 6.83 kNm/g and the tear index to 7.53 mN.m2/g. The tensile and tear index in LMS2 decreased compared to LMS1, but it was still higher than without treatment. Thus, laccase treatment in the refining process can increase the tensile index and tear indexof the sheet.

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