Jafar Ebrahimpour Kasmani; Ahmad Samariha; Alireza Khakifirooz
Abstract
This study aimed to investigate the use of cellulose nanofibers and starch-nano-cellulose and polyacrylamide-nano-cellulose hybrid systems for the replacement of imported long chemical fibers in the production of these papers. In this study, imported long fiber chemical pulp was added to cotton pulp ...
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This study aimed to investigate the use of cellulose nanofibers and starch-nano-cellulose and polyacrylamide-nano-cellulose hybrid systems for the replacement of imported long chemical fibers in the production of these papers. In this study, imported long fiber chemical pulp was added to cotton pulp at 4 levels. Cellulose nanofibers were added to cotton pulp at a 5% level with 1% starch and 0.1% with polyacrylamide. Three levels of cationic starch and three levels of cationic polyacrylamide were also used. From each of the treatments, 60 gm-2 handsheet were made finally the physical, mechanical and optical properties of the paper made from different pulps were compared. The results showed that with increasing nanocellulose individually, compared to imported long fibers, surface smoothness, tensile strength, bursting, tearing of paper increased and air resistance, folding resistance and opacity decreased. Increasing nanocellulose in combination with cationic polyacrylamide increased the paper air resistance and surface area, tensile, burst, tear, and folding strength of the paper compared to imported long fibers, air resistance and opacity. With the increase of nanocellulose in combination with cationic starch, as compared to imported long fibers, surface smoothness, tensile strength, bursting, folding increased but opacity decreased. FE-SEM results also showed that with increasing percentage of cellulose nanofibers, the pores decreased significantly. As a result of the addition of 5% cellulose nanofibers the surface of the paper became smoother and the pores were filled relatively, confirming the results of surface smoothness and air resistance.
Pulp and paper
Yaghob Mamizadeh; Jafar Ebrahimpour Kasmani
Abstract
In textile industry the bellow comb fibers are located in a range in terms of their length and diameter that it can be used as proper raw material especially in paper dough industries; therefore, present study tries to consider improvement of durable paper's properties made of cellulosic nanofibers. ...
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In textile industry the bellow comb fibers are located in a range in terms of their length and diameter that it can be used as proper raw material especially in paper dough industries; therefore, present study tries to consider improvement of durable paper's properties made of cellulosic nanofibers. In this consideration, the below comb fiber of pulp and paper imported chemical pulp are prepared from a company that is producing durable papers and they were transferred to laboratory. Cellulosic nanofiber has been prepared from Nano Novin Polymer Co., and it has been consumed at 4 levels of 0, 0.3, 0.6 and 0.6%. After mixing pulp with cellulosic nanofiber at determined percentages, the handmade 90 g.m-1 papers were made and eventually physical and mechanical properties of these papers were evaluated. The results showed that enhancement of cellulosic nanofibers till 0.9% has led to enhancement of tensile strength, bursting resistance, tearing strength and folding strength comparing to control sample up to 22.7, 38.9, 7.7 and 384% respectively. Increasing the amount of cellulosic nanofibers up to 0.9% the surface smoothness has increased up to 7.9% comparing to control; moreover, water absorption and pores were reduced as 69 and 7.9% respectively. The SEM results showed that enhancement of cellulosic nanofiber percentage has led to reduction of pores.
Pulp and paper
Alireza Khakifiroz; Seeyed Ahmad Mirshokraie; Amir homman Hamasi; Hababalah Khadmieslam; Mohammad Talaei poor
Abstract
Permanent or durable paper is a kind of paper that has a high degree of permanence and is likely to retain the properties which influence readability and document handling when storing in a protected environment for a long period. Permanence depends mainly on the chemical stability of the paper itself. ...
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Permanent or durable paper is a kind of paper that has a high degree of permanence and is likely to retain the properties which influence readability and document handling when storing in a protected environment for a long period. Permanence depends mainly on the chemical stability of the paper itself. Stability may be impaired by chemical reactions involving the paper's own components and by reactive agents from the environment and human being i.e., from air or filing enclosures. Poor chemical stability produces a chain reaction which in long term storage has a pronounced adverse effect on the mechanical or optical properties of the document. The main reactions causing mechanical deterioration are acid hydrolysis and oxidation. Yellowing is due to photochemical and thermal processes. Whatever the fibers used to make paper are longer , alkaline paper making is used , cationic elements such as Fe+2, Fe+3, Cu+2, Mn+2 and kappa number of pulp are minor, it is expected that the paper made is more permanent .In this research imported bleached Eucalyptus kraft pulp was used. The used pulp was refined according to tappi test method T248 cm-85 with PFI mill to reach freeness (300±25) CSF at number of beating revolutions 12000 .Hand sheets were made according to SCAN C25-65 standard with grammage 70.AKD sizing were used 2% oven dry weight of pulp and EDTA as chelating agent was used in concentrations 0 , 0.25 , 0.5 , 0.75 percent. For more assurance deionized water was used. furthermore, 20% calcium carbonate was used as residual alkaline and filler. Then hand sheets were laid under U.V radiation with wavelengths between 330 to 440 nm in 0,10, 20, 30, 40 and 50 hours interval and were conditioned in controlled temperature and relative humidity . pH of Extractive solutions were adjusted between 7 to 7.5 . At last, each strength indices were measured with three measurement frequencies and to compare the amount of mean strengths of produced handsheets, variation analysis (ANOVA) and Duncan test were used with SPSS software and the charts were drawn with Excel software.
