Search
Use the search bar or filters below to find any TAPPI product or publication.
Filters
Content Type
Publications
Level of Knowledge
Committees
Collections
Journal articles
Magazine articles
SetPoint: Reach Out and Touch Someone, Paper360º July/August 2020
SetPoint: Reach Out and Touch Someone, Paper360º July/August 2020
Journal articles
Magazine articles
Social Influence—A Prime Driver of Workplace Safety, Paper360º July/August 2020
Social Influence—A Prime Driver of Workplace Safety, Paper360º July/August 2020
Journal articles
Magazine articles
Paper Machine Water Efficiency, Paper360º July/August 2020
Paper Machine Water Efficiency, Paper360º July/August 2020
Journal articles
Magazine articles
Industrial LED Lighting Improves Pulp & Paper Mill Safety, Paper360º July/August 2020
Industrial LED Lighting Improves Pulp & Paper Mill Safety, Paper360º July/August 2020
Journal articles
Magazine articles
TAPPI Journal Summaries, Paper360º July/August 2020
TAPPI Journal Summaries, Paper360º July/August 2020
Journal articles
Magazine articles
Invisible Waste in Maintenance Organizations, Paper360º July/August 2020
Invisible Waste in Maintenance Organizations, Paper360º July/August 2020
Journal articles
Magazine articles
TAPPI News, Paper360º July/August 2020
TAPPI News, Paper360º July/August 2020
Journal articles
Magazine articles
ASPI News, Paper360º July/August 2020
ASPI News, Paper360º July/August 2020
Journal articles
Magazine articles
Cationic emulsions of maleic anhydride derivatives of oleic and abietic acid for hydrophobic sizing of paper, TAPPI Journal 2020
ABSTRACT: Ordinary rosin sizing agents are mixtures of resin acids that include abietic acid and related compounds obtained from softwoods such as pine. Fatty acids, which are another byproduct of the kraft pulping of soft-wood species, also may have hydrophobic effects, but their use as sizing agents has seldom been considered. In the current study, abietic acid and oleic acid, in the absence of other components, were first modified by reaction with maleic acid anhydride. Then, the maleated derivatives (maleated oleic acid [MOA] and maleated abietic acid [MAA]), which were emulsified with cationic starch at the 1:1 and 3:2 ratio, respectively, were added to fiber furnish containing aluminum sulfate (papermaker’s alum). The prepared sheets were dried with a rotating drum on one side at 100°C at low pressure to cure the sizing agents. The chemical, optical strength, and absorption properties were measured. The presence of the sizing material was confirmed using time of flight secondary ion mass spectrometry (ToF-SIMS), and the retention of the sizing agent on fibers was supported by evidence of hydrocarbons on the paper surface. In addition to achieving sufficient water resistance features with MAA, a lesser hydrophobic character was obtained when using MOA. Compared to commercial applications, relatively large amounts of sizing agent were used to obtain a sufficient sizing degree. The MOA required 5% addition to achieve a similar sizing degree as MAA at the 2% level. The sizing treatments also resulted in substantial increases in tensile index value. Since cationic starch was used in the formulation of the sizing agents, the increase in tensile index may have been due to the influence of cationic starch. Contributions to paper strength from a combination of ionic complexation and mutual association of hydrophobic groups is also proposed. Depending on the amount of sizing agent, the yellowness increased, especially when sizing with MOA.
Journal articles
Magazine articles
Development of a fast brightness testing method for mechanical pulp based on microwave oven drying, TAPPI Journal June 2020
ABSTRACT: Brightness is an important quality parameter for pulp products, and it is important to have reliable measurement of pulp brightness in a timely manner for process control and/or quality control purposes. In these circumstances, a quick testing method for pulp brightness is highly desirable.A rapid handsheet brightness testing method for lignin-rich mechanical pulp has been developed, which is based on the use of tap water to make handsheets and microwave ovens to rapidly dry the handsheet. Microwave oven fast drying decreased the handsheet brightness of mechanical pulp by 5•6 points due to the lignin-originated discol-oration reactions. The spray of ascorbic acid and ethylenediaminetetraacetic acid (EDTA) solutions to the handsheet can effectively inhibit these lignin discoloration reactions.With 0.2% ascorbic acid and 0.2% EDTA spraying on the wet pulp handsheet, the brightness of the handsheet from a peroxide-bleached stone groundwood pulp after the microwave oven fast drying method was similar to that obtained from the same pulp but following TAPPI Standard Test Method T 272 sp-12 “Forming handsheets for reflectance testing of pulp (sheet machine procedure)”. The effect of handsheet dryness on the handsheet brightness was also studied, and the results showed that the brightness reading was almost constant in the dryness range of 70% to 90%. The method developed is a reliable, fast brightness testing method for lignin-rich pulp that is of practical interest in industrial operations.