A moisture-conducting and wear-resistant non-woven fabric for pet urine pads and a method for manufacturing the same

Abstract

The present application relates to a kind of pet urine pad with wet guide wear-resistant nonwoven fabric, by first fiber web and second fiber web are reinforced by water jet;The first fiber web is formed by the skin-core structure bicomponent fiber of spun-bond method, the skin layer of bicomponent fiber is modified polypropylene, and the core layer is polypropylene;The second fiber web is formed by bamboo pulp fiber by direct laying;The modified polypropylene is prepared by grafting modification of polypropylene with acrylate polyether silane, aromatic unsaturated acyl halide melt fusion;The first fiber web of wear-resistant, hydrophobic and soft is prepared by the skin-core structure bicomponent fiber of modified propylene and polypropylene, the second fiber web is prepared by bamboo pulp fiber with good hydrophilicity;After the composite of two, it is reinforced by water jet to form nonwoven fabric, when using, the first fiber web is upward, because the difference between the hydrophilic and hydrophobic of two fiber webs is big, differential capillary effect is formed, so as to realize wet guide function;Because the first fiber web is wear-resistant and soft, simultaneously realizes wear resistance and skin friendliness.

Description

Technical Field

[0001] This invention belongs to the field of nonwoven fabric technology, specifically relating to a moisture-wicking and abrasion-resistant nonwoven fabric for pet diaper pads and its preparation method. Background Technology

[0002] Nonwoven fabrics, also known as non-woven textiles, are composed of oriented or randomly arranged fibers. Due to their good breathability and softness, they are widely used in medical and health products, industrial and agricultural products, and other fields. Polypropylene nonwoven fabrics are widely used due to their lightweight and good mechanical properties. However, polypropylene's regular structure and relatively poor softness and skin-friendliness limit its application in certain areas, such as sanitary napkins, diapers, and changing pads. In particular, nonwoven fabrics for pet changing pads not only require excellent moisture-wicking properties to quickly guide pet urine into the absorbent layer and prevent leakage, but also high abrasion resistance, as pets such as cats and dogs easily scratch and rub against the nonwoven fabric.

[0003] Existing technologies generally improve the skin-friendly softness of polypropylene by modifying it or improving the preparation process. One method for modifying polypropylene to improve skin-friendly softness is the introduction of flexible groups, but this often leads to a decrease in hydrophobicity and abrasion resistance. Improving the preparation process generally has limited effectiveness and is complex. Patents CN102336961B and CN102336929B disclose a PP spunbond nonwoven fabric composite material modified with heavy calcium carbonate and corn starch, and a PP spunbond nonwoven fabric modified with corn starch, respectively. The addition of corn starch reduces the tensile strength of the nonwoven fabric and results in poor abrasion resistance. Patent 117087299A discloses an ultra-low basis weight, high hydrostatic pressure nonwoven fabric and its preparation process. The preparation process includes: preparing a spunbond layer: mixing spunbond layer raw materials according to a ratio, followed by screw extrusion melting, metered spinning, cold air stretching, and web formation to obtain a spunbond layer; a meltblown layer: mixing meltblown layer raw materials according to a ratio, followed by screw extrusion melting, metered spinning, hot air stretching, and web formation to obtain a meltblown layer; a five-layer fiber web structure consisting of two spunbond layers, two meltblown layers, and one spunbond layer from the outside to the inside, and hot-rolling the five-layer structure for reinforcement to obtain the SSMMS ultra-low basis weight, high hydrostatic pressure nonwoven fabric. The improvements in raw materials and processes give this nonwoven fabric good mechanical properties and strength, as well as ultra-low basis weight and high hydrostatic pressure characteristics, but improvements in skin-friendly softness are not addressed.

[0004] Therefore, it is necessary to develop a nonwoven fabric for pet diaper pads that combines moisture-wicking, abrasion-resistant, and soft properties. Summary of the Invention

[0005] In view of the problems that existing nonwoven fabrics for pet diaper pads have, such as insufficient abrasion resistance and difficulty in simultaneously achieving moisture wicking and skin-friendly softness, this invention provides a moisture-wicking and abrasion-resistant nonwoven fabric and its preparation method. This invention uses modified propylene and polypropylene (PP) to form a web through a core-sheath structure via bicomponent spinning and spunbonding, resulting in a first fiber web with good mechanical strength, hydrophobicity, and softness. A second fiber web is prepared by directly laying hydrophilic bamboo pulp fibers onto the web. The first and second fiber webs are then reinforced by hydroentangling to obtain the moisture-wicking and abrasion-resistant nonwoven fabric for pet diaper pads. The second fiber web of the moisture-wicking and abrasion-resistant nonwoven fabric can be laminated with a film (such as a PE film) to produce a pet diaper pad. When in use, the first fiber web faces upward and is in direct contact with the pet. Due to the large difference in hydrophilicity and hydrophobicity between the two fiber webs, a differential capillary effect is formed, which allows the pet's urine and other excrement to be quickly guided into the second fiber web, thereby preventing urine leakage and achieving the moisture-wicking function. At the same time, the first fiber web has good mechanical strength and is soft, achieving good abrasion resistance and skin-friendliness.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A moisture-wicking and abrasion-resistant nonwoven fabric for pet diaper pads is formed by hydroentangling a first fiber web and a second fiber web. The first fiber web is formed by spunbonding bicomponent fibers with a core-sheath structure. The sheath of the bicomponent fibers is modified polypropylene, and the core is polypropylene. The second fiber web is formed by direct web laying of bamboo pulp fibers. The modified polypropylene is obtained by melt co-grafting modification of polypropylene with acrylate polyether silane and aromatic unsaturated acyl halide.

[0008] Furthermore, in the preparation of modified polypropylene, the mass ratio of polypropylene, acrylate polyether silane, and aromatic unsaturated acyl halide is 100:(20-35):(3-7), preferably 100:(25-30):(3-5).

[0009] Furthermore, the melt index of the polypropylene is 25–40 g / 10 min.

[0010] Further, the acrylate polyether silane is a compound containing acrylate groups, polyether segments, and silane groups, wherein the silane groups are methoxysilanes or ethoxysilanes, and the number-average molecular weight of the polyether segments is 1000-2000, for example, selected from at least one of acrylate-polyethylene glycol 1000-silane (AC-PEG1000-Silane), acrylate-polyethylene glycol 1500-silane (AC-PEG1500-Silane), and acrylate-polyethylene glycol 2000-silane (AC-PEG2000-Silane). If the molecular weight of the polyether segments is too low, the grafted chains are too short and the silane group content is too high, failing to achieve the required flexibility and skin-friendly feel; if the molecular weight of the polyether segments is too high, the grafted chains are too long, affecting flowability and strength properties.

[0011] Furthermore, the aromatic unsaturated acyl halide is at least one of cinnamyl chloride, p-styrenesulfonyl chloride, and 4-vinylbenzoyl chloride.

[0012] Furthermore, the modified polypropylene is prepared by the following steps: polypropylene chips, acrylate polyether silane, aromatic unsaturated acyl halide and initiator are mixed evenly and then melt-grafted to obtain modified polypropylene.

[0013] Preferably, the initiator is at least one of dicumyl peroxide and ditert-butyl peroxide, and the amount of initiator used is 0.1-0.2 wt% of the polypropylene chips. The melt grafting conditions are: carried out in a twin-screw extruder at a reaction temperature of 200-220°C and a rotation speed of 70-80 r / min. After the reaction is completed, the product is cooled and pelletized to obtain modified polypropylene.

[0014] Furthermore, the core-sheath structure is either concentric or eccentric, preferably concentric; in the bicomponent fibers of the core-sheath structure, the sheath layer accounts for 10wt% to 30wt%.

[0015] Furthermore, the fineness of the bicomponent fibers in the core-sheath structure is 1.5–2.5 dtex, the fineness of the bamboo pulp fibers is 1.0–1.5 dtex, and the length is 30–50 mm; the basis weight of the first fiber web is 8–15 g / m². 2 The basis weight of the second fiber is 15–25 g / m². 2 .

[0016] Secondly, the present invention also provides a method for preparing the above-mentioned moisture-wicking and abrasion-resistant nonwoven fabric for pet diaper pads, comprising the following steps:

[0017] (S1) First fiber web: Modified polypropylene and polypropylene are fed into two sets of extruders for heating and melting, and then enter the skin cavity and core cavity of the composite component of the bicomponent spinning box through melt filter and metering pump respectively; composite spinning is carried out at the outlet to form bicomponent fiber filaments with a skin-core structure. The filaments are cooled by side blowing, drawn at high speed by tubular drawing device, and laid into web to obtain the first fiber web;

[0018] (S2) Second fiber web: The bamboo pulp fibers are opened, combed, and laid out in parallel to form a second fiber web;

[0019] (S3) Hydroentangling reinforcement: The first fiber web and the second fiber web are fed into the composite web forming system for composite superposition, and then reinforced by hydroentangling, dried and rolled to obtain the moisture-wicking and wear-resistant nonwoven fabric for pet diaper pads.

[0020] Furthermore, the temperature of the composite spinning in step (S1) is 220-260°C, preferably 240-250°C.

[0021] Furthermore, the conditions for hydroentanglement reinforcement in step (S3) are: hydroentanglement pressure of 5-10 MPa and number of hydroentanglements of 3-6.

[0022] Polypropylene has a regular structure and no polar groups on its surface, resulting in good hydrophobicity. However, its skin affinity and softness are lacking, and modification for softness generally leads to a decrease in hydrophobicity and abrasion resistance. This invention involves melt co-grafting polypropylene with acrylate polyether silane and aromatic unsaturated acyl halides, grafting flexible long polyether chains, silane groups, and acyl halide groups onto the polypropylene macromolecular chains. The long-chain polyether groups possess good flexibility, improving the softness of polypropylene; the silane groups possess good hydrophobicity, improving the hydrophobicity of polypropylene and thus compensating for the decrease in hydrophobicity caused by the introduction of the polyether segment; furthermore, aromatic unsaturated acyl halides are small-molecule rigid substances, and their acyl chloride groups can react with silaneoxy groups to form localized rigid cross-linking in the flexible long grafted chains, thereby improving the mechanical properties of the modified polypropylene. The synergistic effect of acrylate polyether silane and aromatic unsaturated acyl halides in a certain proportion allows the modified polypropylene to maintain good hydrophobicity and abrasion resistance while possessing good skin affinity. However, the aforementioned modified polypropylene fibers are costly. This invention reduces costs by composite spinning modified polypropylene and polypropylene in a core-sheath structure to create a core-sheath bicomponent fiber. The core-sheath bicomponent fiber is a composite fiber with two components arranged in a core-sheath configuration. It is composed of two polymers with different properties, one component surrounding the other along the fiber axis, combining the characteristics of both fibers. In this invention, polypropylene serves as the core layer, providing high tensile strength; modified polypropylene serves as the sheath layer, directly contacting the skin, maintaining good hydrophobicity and abrasion resistance while providing good softness. Simultaneously, due to the difference in heat shrinkage properties between modified and unmodified polypropylene, different degrees of shrinkage occur during spinning, resulting in three-dimensional helical crimp, further enhancing fluffiness and softness. Thus, the first fiber web produced by spunbonding the modified polypropylene / polypropylene bicomponent fiber maintains good hydrophobicity and abrasion resistance while possessing good skin-friendly softness.

[0023] Bamboo pulp fiber has excellent moisture absorption capacity. When used as the second fiber web, it is combined with the first fiber web to form a composite nonwoven fabric with a hydrophobic layer and a hydrophilic layer. The differential capillary effect and wetting gradient effect create an additional pressure difference in the thickness direction of the nonwoven fabric, which allows pet urine and other excrement to be quickly guided into the second fiber web, thereby preventing urine leakage and achieving the moisture-wicking function. At the same time, the first fiber web has good mechanical strength and softness, thus achieving good abrasion resistance and skin-friendliness.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] 1. This invention first obtains modified polypropylene by melt co-grafting polypropylene with acrylate polyether silane and aromatic unsaturated acyl halide; then, the modified polypropylene and polypropylene are spun together in a core-sheath structure using a two-component spinning and spunbonding method to form a web, resulting in a wear-resistant, hydrophobic, and soft first fiber web; next, the first fiber web is composited with a second fiber web composed of bamboo pulp fibers and reinforced by a hydroentangling process to obtain a moisture-wicking and wear-resistant nonwoven fabric for pet diaper pads. During use, the first fiber web faces upwards and is in direct contact with the pet. Due to the significant difference in hydrophilicity and hydrophobicity between the two fiber webs, a differential capillary effect is formed, allowing the pet's urine and other excrement to be quickly guided into the second fiber web, thus preventing urine leakage and achieving the moisture-wicking function; simultaneously, because the first fiber web is wear-resistant and soft, it achieves both good wear resistance and skin-friendliness.

[0026] 2. This invention combines spunbond technology with hydroentanglement technology, resulting in high production efficiency. Detailed Implementation

[0027] The present invention will be further described below with reference to specific embodiments, but is not limited to the contents of the specification. Unless otherwise specified, all "parts" mentioned in the embodiments of the present invention are parts by weight. All reagents used are commercially available in the art.

[0028] Polypropylene chips were purchased from Beijing Yanshan Petrochemical Corporation, with a melt flow index of 38±1g / 10min.

[0029] The bamboo pulp fiber was purchased from Shandong Jiumian Textile Co., Ltd., and it measures 1.33 dtex × 38 mm.

[0030] AC-PEG600-Silane, AC-PEG1000-Silane, AC-PEG2000-Silane, and AC-PEG3000-Silane are all acrylate polyether trimethoxysilanes, industrial grade, and sourced from Xi'an Qiyue Biotechnology Co., Ltd. The number average molecular weight of the polyethylene glycol segments in AC-PEG600-Silane is 600, in AC-PEG1000-Silane it is 1000, in AC-PEG2000-Silane it is 2000, and in AC-PEG3000-Silane it is 3000.

[0031] Methoxylated polyethylene glycol (1000) acrylate, selected from Guangzhou Haoyi New Material Technology Co., Ltd., model number MPEG1000A.

[0032] Preparation of modified polypropylene

[0033] Preparation Example 1

[0034] 100 parts of polypropylene chips, 20 parts of AC-PEG1000-Silane, 3 parts of cinnamoyl chloride and 0.15 parts of dicumyl peroxide were mixed evenly and then subjected to a melt grafting reaction in a twin-screw extruder at 200°C with a screw speed of 80 r / min. The reaction extrudate was cooled with water and granulated by a pelletizer to obtain modified polypropylene.

[0035] Preparation Example 2

[0036] The rest is the same as in Preparation Example 1, except that the amount of AC-PEG1000-Silane used is 25 parts.

[0037] Preparation Example 3

[0038] The rest is the same as in Preparation Example 1, except that the amount of AC-PEG1000-Silane used is 30 parts and the amount of cinnamoyl chloride used is 5 parts.

[0039] Preparation Example 4

[0040] The remaining differences compared to Preparation Example 1 are as follows: the amount of AC-PEG1000-Silane used is 35 parts and the amount of cinnamoyl chloride used is 7 parts.

[0041] Preparation Example 5

[0042] The remaining differences compared to Preparation Example 1 are: AC-PEG2000-Silane was used instead of AC-PEG1000-Silane, and 4-vinylbenzoyl chloride was used instead of cinnamoyl chloride.

[0043] Preparation Example 6

[0044] The remaining differences compared to Preparation Example 1 are: AC-PEG600-Silane was used instead of AC-PEG1000-Silane.

[0045] Preparation Example 7

[0046] The remaining differences compared to Preparation Example 1 are: AC-PEG3000-Silane was used instead of AC-PEG1000-Silane.

[0047] Comparative Preparation Example 1

[0048] The remaining differences compared to Preparation Example 1 are: AC-PEG1000-Silane was replaced by methoxy polyethylene glycol (1000) acrylate (MPEG1000A) by mass.

[0049] Comparative Preparation Example 2

[0050] The only difference from Preparation Example 1 is that cinnamyl chloride is not used.

[0051] Example 1

[0052] (S1) First Fiber Web: 10 kg of the modified polypropylene prepared in Example 1 was fed into an extruder for heating and melting, and then passed through a melt filter and a metering pump into the sheath cavity of the composite component in the bicomponent spinning box; simultaneously, 90 kg of polypropylene was added to the extruder for heating and melting, and then passed through a melt filter and a metering pump into the core cavity of the composite component in the bicomponent spinning box; composite spinning was performed at the outlet (spinning temperature was 245°C) to form a bicomponent fiber filament with a core-sheath structure. The filament was cooled by side blowing, drawn at high speed by a tubular drawing device, and laid into a web to obtain a fineness of 2.1 dtex and a basis weight of 12 g / m². 2 The first fiber web;

[0053] (S2) Second Fiber Web: The bamboo pulp fibers are opened, combed, and laid out in parallel to form a web with a basis weight of 25g / m². 2 The second fiber web;

[0054] (S3) Hydroentangling reinforcement: The first fiber web and the second fiber web are fed into the composite web forming system for composite superposition, and then reinforced by hydroentangling (hydroentangling pressure 7Mpa, number of hydroentangling channels 5), dried and rolled up to obtain the moisture-wicking and wear-resistant nonwoven fabric for pet diaper pads.

[0055] Examples 2-7

[0056] The rest is the same as in Example 1, except that the modified polypropylene was prepared in Examples 2-7.

[0057] Example 8

[0058] The rest is the same as in Example 1, except that: in step (S1), the amount of modified polypropylene is 30 kg and the amount of polypropylene is 70 kg.

[0059] Comparative Examples 1-2

[0060] The rest is the same as in Example 1, except that the modified polypropylene was prepared in Comparative Preparation Examples 1-2.

[0061] Testing and Analysis

[0062] The pet diaper pads prepared in the above embodiments and comparative examples were subjected to the following performance tests using moisture-wicking and abrasion-resistant nonwoven fabrics, and the results are shown in Table 1.

[0063] Liquid penetration time: Measured according to standard GB / T 24218.8. The shorter the penetration time, the better the moisture-wicking performance.

[0064] Softness: The transverse softness and longitudinal softness are measured in accordance with the standard GB-T 8942-2016. The larger the value, the worse the softness.

[0065] Abrasion resistance: The test shall be conducted in accordance with the provisions of GB / T 21196.2-2007 "Textiles - Martindale Method - Determination of Abrasion Resistance of Fabrics - Part 2: Determination of Specimen Breakage". The test conditions are: friction load of 5 kPa, standard wool felt; record the total number of frictions when the specimen breaks to determine its abrasion resistance. The higher the total number of frictions when the specimen breaks, the better the abrasion resistance.

[0066] Table 1 Performance Tests

[0067]

[0068]

[0069] As can be seen from Table 1, the nonwoven fabric prepared in the embodiments of the present invention has good moisture wicking and abrasion resistance, and is also skin-friendly and soft. The nonwoven fabric prepared in Comparative Example 1 has good softness, but poor abrasion resistance and moisture wicking. The nonwoven fabric prepared in Comparative Example 2 has good moisture wicking and softness, but poor abrasion resistance.

[0070] The above detailed description is a specific description of one of the feasible embodiments of the present invention. This embodiment is not intended to limit the patent scope of the present invention. All equivalent implementations or modifications that do not depart from the present invention should be included within the scope of the technical solution of the present invention.

Claims

1. A moisture-wicking and abrasion-resistant nonwoven fabric for pet diaper pads, comprising a first fiber web and a second fiber web reinforced by hydroentangling; characterized in that, The first fiber web is formed by spunbonding of bicomponent fibers with a core-sheath structure. The sheath of the bicomponent fiber is modified polypropylene, and the core is polypropylene. The second fiber web is formed by direct web laying of bamboo pulp fibers. The modified polypropylene is obtained by melt co-grafting modification of polypropylene with acrylate polyether silane and aromatic unsaturated acyl halide. In the preparation of the modified polypropylene, the mass ratio of polypropylene, acrylate polyether silane, and aromatic unsaturated acyl halide is 100:(20~35):(3~7). The acrylate polyether silane is a compound containing acrylate groups, polyether segments, and siloxane groups, wherein the siloxane groups are methoxysilane or ethoxysilane, and the number average molecular weight of the polyether segments is 1000~2000.

2. The moisture-wicking and abrasion-resistant nonwoven fabric for pet diaper pads according to claim 1, characterized in that, In the preparation of modified polypropylene, the mass ratio of polypropylene, acrylate polyether silane, and aromatic unsaturated acyl halide is 100:(25~30):(3~5).

3. The moisture-wicking and abrasion-resistant nonwoven fabric for pet diaper pads according to claim 1, characterized in that, The melt index of the polypropylene is 25~40 g / 10 min.

4. The moisture-wicking and abrasion-resistant nonwoven fabric for pet diaper pads according to claim 1, characterized in that, The aromatic unsaturated acyl halide is at least one of cinnamyl chloride, p-styrenesulfonyl chloride, and 4-vinylbenzoyl chloride.

5. The moisture-wicking and abrasion-resistant nonwoven fabric for pet diaper pads according to claim 1, characterized in that, The modified polypropylene is prepared by the following steps: polypropylene chips, acrylate polyether silane, aromatic unsaturated acyl halide and initiator are mixed evenly and then melt-grafted to obtain modified polypropylene.

6. The moisture-wicking and abrasion-resistant nonwoven fabric for pet diaper pads according to claim 5, characterized in that, The initiator is at least one of dicumyl peroxide and ditert-butyl peroxide, and the amount of initiator used is 0.1~0.2wt% of polypropylene chips; the melt grafting conditions are: carried out in a twin-screw extruder, with a reaction temperature of 200~220℃ and a rotation speed of 70~80r / min.

7. The moisture-wicking and abrasion-resistant nonwoven fabric for pet diaper pads according to claim 1, characterized in that, The core-sheath structure is either concentric or eccentric; in the bicomponent fibers of the core-sheath structure, the sheath layer accounts for 10wt%~30wt%; and / or The bicomponent fibers of the core-sheath structure have a fineness of 1.5~2.5 dtex, the bamboo pulp fibers have a fineness of 1.0~1.5 dtex, and a length of 30~50 mm; the basis weight of the first fiber web is 8~15 g / m². 2 The basis weight of the second fiber is 15~25 g / m². 2 .

8. The moisture-wicking and abrasion-resistant nonwoven fabric for pet diaper pads according to claim 7, characterized in that, The core-skin structure is concentric.

9. The method for preparing the moisture-wicking and abrasion-resistant nonwoven fabric for pet diaper pads according to any one of claims 1-8, characterized in that, Includes the following steps: (S1) First fiber web: Modified polypropylene and polypropylene are fed into two sets of extruders for heating and melting, and then enter the skin cavity and core cavity of the composite component of the bicomponent spinning box through melt filter and metering pump respectively; composite spinning is carried out at the outlet to form bicomponent fiber filaments with skin and core structure. The filaments are cooled by side blowing, drawn at high speed by tubular drawing device and laid into web to obtain the first fiber web; (S2) Second fiber web: The bamboo pulp fibers are opened, combed, and laid out in parallel to form a second fiber web; (S3) Hydroentangling reinforcement: The first fiber web and the second fiber web are fed into the composite web forming system for composite superposition, and then reinforced by hydroentangling, dried and rolled to obtain a moisture-wicking and wear-resistant nonwoven fabric for pet diaper pads.

10. The preparation method according to claim 9, characterized in that, The temperature of the composite spinning in step (S1) is 220~260℃; the conditions for hydroentangling reinforcement in step (S3) are: hydroentangling pressure 5~10Mpa, and the number of hydroentangling passes 3~6.

Images