Paper tensile properties

In the pulp and paper industry, anionic and cationic acrylamide polymers are used as chemical additives or processing aids. The positive effect is achieved due to a fuller retention of the filler (basically kaoline) in the paper pulp, so that the structure of the paper sheet surface layer improves. Copolymers of acrylamide with vi-nylamine not only attach better qualities to the surface layer of.paper, they also add to the tensile properties of paper in the wet state. Paper reinforcement with anionic polymers is due to the formation of complexes between the polymer additive and ions of Cr and Cu incorporated in the paper pulp. The direct effect of acrylamide polymers on strength increases and improved surface properties of paper sheets is accompanied by a fuller extraction of metallic ions (iron and cobalt, in addition to those mentioned above), which improves effluent water quality. 

Supply is related to cost. If basic materials become scarce, changes will follow. Thus constraints in the petroleum supply may affect the polymer industry, which is based almost entirely on petrochemicals. We can look for expanded use of paper-based materials to provide factors such as bulk, tensile properties, and thermal resistance combined with the low weights of proper barrier materials. Composites will continue to grow in quantity and complexity. 

Swelling tests and determination of tensile properties. The procedure for estimating cross-link density from equilibrium swelling data is described in detail in a previous paper (6). The tensile properties of the PU films were carried out at 23°C and 60% relative humidity. The crosshead speed and distance were 10 mm/min and 30 mm, respectively. A more detailed description of the tensile tests is given elsewhere (6). 

To determine the effect of coating thickness on tensile properties, coating thicknesses of 0.25, 0.5, 0.75, 0.85, 1.0, 1.25 and 1.5 im of Parylene-C were applied to modern silk fabric. In Table 2, the breaking-load and strain-to-break are shown as a function of coating thickness, and a linear dependence is evident. A similar effect was observed when paper was coated with Parylene-C (5). 

Runnability is often expressed as the number of paper web breaks per 100 rolls. Paper web breaks during press runs are very costly in terms of money and time. Thus, high-speed newsprint presses also require newsprint with good tensile properties. Although the tensions in newsprint presses are kept well below the average tensile strengths of the paper, breaks do occur. These are generally the result of some defect in the paper such as shives that are not removed from the mechanical pulp fraction of newsprint. 

The individual fiber properties which contribute to the tensile properties of paper include the following (8) fiber tensile strength mean fiber length fiber cross-sectional area perimeter of the average fiber cross section density of the fibrous material fraction of the fiber area bonded in the sheet and the shear strength per unit area of fiber-to-fiber bonds. 

Metals in pulps and papers were determined after wet-ashing with nitric acid by atomic absorption techniques using a commercial instrument. Tensile properties (load at break, elongation at break, energy to break) were determined using a commercial recording load-elongation machine (45),... 

Table XII. Tensile Properties of Old Papers after Soaking in Water or in 0.05M Mg(HC03)2...

South Korean company SK Chemicals produces SKYGREEN polybutylene succinate (PBS) thermoplastics based on aliphatic polyester and aliphatic/aromatic co-polyesters that were developed from SK Chemicals polyethylene terephthalate (PET) technology. SKYGREEN BDP products offer LDPE-like properties. They are used in films, disposable cutlery, food trays, hairbrush handles and paper coatings. Aliphatic versions biodegrade more rapidly and offer better processing and tensile properties than the aromatic-aliphatic grades, which cost less. 

S Yano, H Hatakeyama, T Hatakeyama. Temperature dependence of the tensile properties of lignin/paper composites. Polym 25 890-893, 1984. 

Polymethylpentene Thermoplastie stereoregular polyolefin obtained by polymerizing 4-methyl-1-pentene based on dimerization of propylene has low density, good transpar-eney, rigidity, dieleetrie and tensile properties, and heat and ehemieal resistanee. Proeessed by injection and blowmolding and extrusion. Used in laboratory ware, coated paper, light fixtures, auto parts, and electrical insulation. Also called PMP. 

This paper was originally published in the Journal of Applied Physics, Vol. 50, No. 10, Part II imder the title "Modeling of Tensile Properties of Polymer Blends PPO/Poly(styrene-co-p-chlorostyrene". 1979 American Institute of Physics. 

In this paper, an attempt is made to relate the mechanical (tensile) properties of a family of related polyblends to the state of compatibility of the blend. The prototype compatible blend studied is that of poly (2,6-dimethy1-1, 4-phenylene oxide)(PPO) and polystyrene (PS). Evidence for the compatibility of PPO and PS is substantial and is reviewed elsewhere (5). Films molded from blends of PPO and PS are optically clear and exhibit a single composition dependent glass transition temperature (Tg). 

This paper focuses on the mathematical modelling of the relationship between the mechanic and elastic properties of these 2 novel materials. It has been found that both materials offer a quasi linear relationship between load and di lacement vdien tested for their tensile properties. The two novel spacers also offer very similar curves for the relationship between limb circumference and percentage reduction in matraial s width during manufacture in order to obtain optimum compression of IS.S mmHg around the knee. 

By far the greatest share of both experimental studies of mechanical properties of fibres and theoretical studies of structural mechanics has been on tensile properties. This paper therefore concentrates on explanations of tensile stress-strain curves and the way in which they lead to fracture. Some comments on other forces, particularly in cyclic loading, will be included in a concluding section. 

In this paper, the BPDA-PFMB/PEI molecular composites were oriented by means of zone annealing/drawing slightly above the glass transition temperatures of the respective molecular composites (280 - 400 °C). The dependence of draw ratio on tensile modulus, crystal orientation, and birefringence was determined as a function of composition. The relationship between structure (crystal orientation) and tensile property (modulus) of drawn films has been examined by comparing crystal chain orientations with the prediction of affine deformation (12-16). 

In this paper, we describe the mechanism for formation of epoxy-clay nanocomposites and compare the tensile properties of the intercalated and exfoliated forms of these nanocomposites. 

There have been numerous papers on the mechanical properties of PEEK (16) (58) (59). The tensile properties have been examined... 

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