SU1087596A1 - Mass for making asbestos-latex paper - Google Patents

Abstract

MASS FOR MAKING ASBESTOLATEX PAPER, containing asbestos, sulphate cellulose, synthetic latex and ionic substance, characterized in that, in order to increase paper resistance to bending, its strength and reduce stiffness, as a synthetic latex, it contains vinylidene-choridant type, which is used to increase the resistance of the paper to repeated bending, its strength, and to reduce its stiffness, as a synthetic latex, it contains vinylidene-latex, and is used to provide the same type of body weight, which is used to increase the resistance of the paper to repeated bending, its strength, and to reduce stiffness. 70), and as an ionic substance - an aqueous solution of a polymeric complex of polyacrylic acid and E-caprolactam at a ratio of 1: 1 with the following content of i components, wt.ch .: Asbestos 70.0-90.0 (L Sul phatna cellulose 10.0-30.0 Vinylidenechloride latex (DVHB-70) 30.0-40.0 Polymeric complex of polyacrylic acid and E-caprolactam 0.5-1.5 Water25.0-75.0 00 ate

Description

The invention relates to masses for the manufacture of asbestos-latex paper and can be used for coating pipelines of heat networks, as well as process pipelines. A known mass for the manufacture of asbestos-paper paper on the basis of asbestos, sulphate pulp and latex 1. The disadvantages of a coating material based on it are low strength, cutting out rigidity and low resistance to repeated bending. A pulp for the manufacture of asbestosolatex paper containing asbestos and a polymeric binder — a copolymer of styrene, butadiene, and unsaturated carboxylic acid with 2 is also known. The disadvantages of a coating material based on it are high rigidity and low resistance to multi-edge bending. The closest to the invention in its technical essence is a pulp for making asbestos paper, including sulphate pulp, polymeric binder, synthetic latex, starch, zinc oxide and non-ionic surface active substance - sopal in the following ratio of components, May, h ,; asbestos 65-80; sulphate pulp 12-16; polymeric binding nitrile latex 4-12,5; starch 2-3; zinc oxide 0.9-3; nonionic surfactant 0.20, 6 C3. The disadvantages of the material based on the known mass are low pro- perity, high rigidity and low resistance to repeated bending, which makes it impossible to use it as a coating material for insulating pipelines. The aim of the invention is to increase. The paper's resistance to repeated bending, its strength and decrease in stiffness. The goal is achieved by the fact that the mass for the manufacture of asbestos-latex paper, containing asbestos, sulphate cellulose, synthetic latex and ionic substance, contains synthetic vinyl latex (EHB-70) as a synthetic latex, and a single solution of the polyacrylate acid and E- complex as the ionogenic substance. caprolacta at a ratio of 1: 1 with the following content of components, May, hours: Asbestos 70.0-90.0 Sulfate cellulose 10.0-30.0 Vinylidene chloride latex (DVHB-70) 30.0-40.0 Polyacrylic polymer complex acid and e-capro aktam 0.5-1.5 Voda25,0-75,0 sbestodolateksnuyu paper receive the following technology, Example 1, Obtaining polymeric complex of polyacrylic acid E-caprolactam, Polymeric complex of polyacrylic acid and E-caprolactam is obtained by polymerization of acrylic acid in medium E- caprolactam. The molar ratio of acid and E-caprolactam in the initial mixture of monomers is 1: 1. Dinitrile-arobisisobutyric acid is used as an initiator for the reduction of 0.1% of the yass of acid. The polymerization is carried out at 70-75 seconds for 20 minutes. The polymer complex of polyacrylic acid and E-caprolactam is obtained by the general formula -CH2, -CH-CK -CH-SyHCNI I I. NH - C 0 Example 2, Preparation of a primer binder. Prepare a 2% aqueous solution of a polymeric complex of polyacrylic acid and E-caprolactam, and add it to the latex according to the following recipe, h.: Latex DCCB-7040 Polymer complex PAK-CL 0.5-1.5 Water 25-75 Then the resulting polymer binder is diluted with water to a working concentration of 4% by weight with stirring, stabilized by a solution of a sulfate-yeast brew, which is added in an amount of 8% by weight, the dry residue of latex. 310 Example 3. Preparation of fiber filler. Grinding of cellulose and asbestos is carried out on an aggregate consisting of a 2m-1M hydrothinner and three MKL-01 knife mills. Cooked in filamentous filler is poured into a massive pool. The mass is diluted with water to a concentration of 1.8% by weight. Water consumption is 60 m - per 1 ton of dry wave; the time of fiber mixing is 1520 minutes. Example 4. Impregnation of asbestos and cellulose with a polymeric binder. The fibrous mass is impregnated with a polymeric binder (obtained according to example 3) in the labyrinth of a long-haul machine with continuous stirring with paddle mixers. The deposition of the polymeric binder onto the fiber is carried out by continuous feeding of coagulum. An aqueous solution of alumina, the concentration of which is 30-35 g / l, is used as a coagulant. Example 5. Dehydration of fibrous mass. The dewatering of the fibrous mass in the long-line machine is carried out using suction boxes with a gradual increase in vacuum from 50 to 400 mm Hg. Art. The moisture content of the material before pressing should be no more than 75%, Example 6, Obtaining asbestos latex paper (cover material ala). The paper is pressed on a gauch press, then on direct and reverse presses. The pressure on the presses is 0.6 MPa. After pressing, the moisture content of the material is 65%, the pressed material in the form of a continuous web is fed to the dryer. Example 7. Drying of asbestos-free paper (cover material. The drying of the paper web is carried out in horizontal and drum dryers. The paper passes through three floors of the horizontal dryer using three conveyors. The drying is performed using thermal ventilation with perpendicular air flow direction moving material web simultaneously on both sides of the web. Moisture-saturated air is sucked off by exhaust fans. The final drying of the paper is carried out in a drum A two-sided hot air in the dryer is countercurrent with high and medium speed fans Temperature range horizontally with a full-body dryer, C: 90-120 80-110 80-100 The humidity of the web after the horizontal dryer is 30%. The temperature setting in the drum dryer is 40-80 ° C. The moisture content of the web-paper after drying is 6 + 2%. To compact and give the paper a smooth surface, it is coded and then fed to the winding device. The test results obtained paper (coating material) are presented in table. 1-3. The introduction of a smaller amount of latex (less than 30 parts by weight) to the composition of the paper (coating material) leads to a reduction in dryness both in dry and wet conditions, an increase in the content of latex by more than 40 parts, increases the value of paper , as it depends on latex consumption. The introduction of the paper aqueous solution of the polymer complex PAK-KL more than 1.5 wt.h. leads to partial coaugulation of the latex, and the introduction of a smaller amount (less than 0.5 wt.h.) does not lead to the desired results due to the insufficient amount of the modifying additive in the composition of the polymeric binder. The strength of paper based on the proposed composition increases in both dry and wet conditions by an average of 50 and 40%, respectively, the rigidity is significantly reduced from 54 to 8 and the resistance to repeated bending increases 70 times. This makes it possible to use as a covering material for the insulation of pipelines. Paper properties - coating material (composition of the polymeric binder, mac. Part): Latex DVHB-7040 Polymer complex PAK-KL0.5 Water25

Asbestosolatex paper as a coating material has successfully passed field trials.

The following coating materials are currently used as the composition of the known mass: folgoobrueroid, folgoidol, lekosteklotkan and capandated polyvinyl chloride film, for the manufacture of which scarce and expensive materials are used - aluminum foil and fiberglass. The economic efficiency of replacing these materials with a coating material based on the proposed composition is 434.8 thousand rubles.

Table 1

Strength at break in dry condition, n / mm

Bending stiffness, N

Resistance to multiple bending, thousand cycles

Strength at rupture after soaking in water, n / mm

Relative elongation when stretched in the dry state,

Abrasion, mm / min

The decrease in strength after 25 cycles of freezing and thawing in water,%

The strength of attachment of polymeric binder and fiber filler, MPa

Paper properties - coating material (polymer binder composition, mac.p.): Latex DVHB-7040

Polymeric complex PAK-KL 1,3 Voda75

Strength at rupture in dry condition,, 6

Bending stiffness, H54

42

56

58

0.4

0.58

0.33

Table 2

9.8

13.2

five

five

Elongation at stretching in dry

condition,% Abrasion, mm / min

The decrease in strength after 25 cycles of freezing and thawing in water,%

The strength of attachment of the polymer binder and fiber performer, MPa

Paper properties - coating material (polymer binder composition, mac.p.): Latex DWHB-7030

Polymeric complex PAK-KL 0,5 Voda25

Resistance to multiple bending, thousand cycles

Strength at break after soaking in water, n / mm

Relative elongation when stretched in the dry state.

Abrasion, mm / min

Continued table. 2

24 0.16

20 0.16

12 0.12

54 0.56

44 0.58

52 0.6

Table 3

34 5.4

33 6.9

31 5.1

25 0.19

21

12 0.14 0.18

The decrease in strength after 25 cycles of freezing and thawing in water,%

The strength of attachment of polymeric binder and fiber filler, MPa

1087596

10 Continued table. 3

49

61

59

0.49

0.51

0.5

Claims (1)

MASS FOR MAKING ASBESTOLATEX PAPER containing asbestos, sulphate cellulose, synthetic latex and ionic material, characterized in that, in order to increase the paper's resistance to repeated bending, its strength and reduce stiffness, it contains vinylidene chloride L-latex (D 70), and as an ionic substance - an aqueous solution of a polymer complex of polyacrylic acid and E-caprolactam at a ratio of 1: 1 with the following content components, parts by weight: Asbestos 70.0-90.0 Sulphate cellulose 10.0-30.0 Vinylidene chloride latex (DVHB-70) 30,0-40,0 Polymer complex polyacrylic acid you and E-caprolactam 0.5-1.5 Water 25.0-75.0