KR20130130790A - Brush filaments prepared from a polytrimethylene terephthalate composition and brushes comprising the same - Google Patents

Abstract

Disclosed herein are monofilament bristles made from modified polytrimethylene terephthalate (PTT) compositions, wherein the modified polytrimethylene terephthalate (PTT) compositions comprise (a) 85-95 weight percent polytrimethylene tere Phthalate, and (b) 5 to 15% by weight of polyethylene-alkyl acrylate copolymer, having a flexural modulus of 2500 MPa or less, a tensile modulus of 2600 MPa or less, and an elongation at break of 20% or less.

Description

BRUSH FILAMENTS PREPARED FROM A POLYTRIMETHYLENE TEREPHTHALATE COMPOSITION AND BRUSHES COMPRISING THE SAME}

The present invention relates to monofilament bristle, more specifically monofilament bristle made of polytrimethylene terephthalate composition. The invention also relates to a brush comprising monofilament bristles.

In the field of toothbrushes, paint brushes, cosmetic brushes and the like, monofilament bristles are usually made of chemically synthesized materials such as polybutylene terephthalate (PBT). Due to the unique functional characteristics of the toothbrush, there are some special requirements for selecting the monofilament bristle material used in the toothbrush. For example, polyamide 6,12 is used in toothbrushes because it is soft when in contact, will not harm the teeth, and has good flexural recoverability. However, polyamides are highly hygroscopic; Absorption of water reduces its physical properties and flexural recovery, and its size changes significantly. Thus, when using the toothbrush for some continuous use, the polyamide monofilament bristles spread and spread to each other, thereby reducing their durability. Moreover, using polyamides is more expensive. In addition, due to the high hardness, poor tenacity, high brittleness and high rigidity of polybutylene terephthalate (PBT), it cannot be used directly to manufacture toothbrushes. In the industry, the tips of monofilament bristles made of polybutylene terephthalate are usually sharpened using chemical flux etching techniques and softened prior to use in toothbrushes. This technique undoubtedly increases the cost and causes problems such as environmental pollution by chemical etching solutions.

 Other polyester materials (eg, polyethylene terephthalate (PET)) used to make monofilament bristle products on behalf of polyamide or polybutylene terephthalate have been studied. For example, German Patent Application No. 19937729A1 discloses an industrial high strength polyester yarn comprising polyethylene terephthalate and 0.1 to 2 wt% amorphous copolymer fillers; Japanese Patent Application No. 202020931A discloses a polyester filament for use in handmade paper or canvas straps, the polyester filament comprising polyethylene terephthalate, 1 to 15 weight percent polyethylene-acrylate copolymer and 0.3 to 3.0 weight percent Carbodiimide; U.S. Patent Application No. 20090075543A1 discloses monofilaments for use in the textile or paper industry. This monofilament comprises a biphasic polymer blend, wherein polyethylene terephthalate serves as the first phase and the ethylene copolymer serves as the polymer of the second phase.

Polytrimethylene terephthalate (PTT) is another type of high performance polymer in the field of polymeric synthetic materials. It not only has excellent performance, excellent chemical resistance, elasticity, excellent chlorination and color fastness, but also has advantages such as good pollution resistance, resistance to ultraviolet light, resistance to nitrogen oxides, resistance to ozone, and antistatic. It is one type of thermoplastic polyester having. In addition, 1,3-propylene glycol, which is one of the starting materials used for the production of polytrimethylene terephthalate, can be obtained through biochemical processes, and therefore its application has been attracting much attention and research.

For example, US Pat. No. 6,673,444B2 discloses monofilament forms of copolymers comprising greater than 90 mol% trimethylene terephthalate repeat units and less than 10 mol% other polyester repeat units, wherein the other polyesters Materials capable of forming repeating units include polyethylene terephthalate, polyamides, or dicarboxylic acids and / polyols. This monofilament has excellent softness, bending recovery and durability. This monofilament can be used to weave yarn or bristles.

The application of polytrimethylene terephthalate in the industry of monofilament bristles, in particular in the industry of toothbrush bristles is likewise disclosed, an example of which is US Pat. No. 6,053,734. Specifically, US Pat. No. 6,053,734 discloses monofilament bristles made of polytrimethylene terephthalate, and monofilament bristles having a core-sheath structure. Monofilament bristles having a core-sheath structure include a core formed of a polymer having high flexural elastic modulus, such as polyethylene terephthalate, and a sheath formed of polytrimethylene terephthalate.

In addition, Japanese Patent Application No. 2007-000519 also discloses bristles and toothbrushes made of bristles. The bristles likewise have a core-sheath structure and comprise a core having two or more resin layers coating the core in a concentric manner, wherein the core is made of polytrimethylene terephthalate (PTT) and the outer resin layer is polytri The intermediate layer, made of polyester-based resins other than methylene terephthalate (PTT) (eg, Hytrel® copolyether-ester resin), sandwiched between the core and the outer resin layer is poly It is made of a blend of the above polyester-based resins other than trimethylene terephthalate and polytrimethylene terephthalate. The function of the intermediate resin layer is to provide adhesion between the core of the bristles and the outer layer.

Although polytrimethylene terephthalate has been used in the prior art to produce monofilament bristles, the inventors of the present application have shown that the hardness of polytrimethylene terephthalate in view of its application in toothbrushes, paint brushes, cosmetic brushes or industrial brushes. Is still high, and due to its poor toughness and high brittleness, it is additionally necessary to provide a modified product with the ability to simultaneously meet the needs of monofilament bristles with various physical properties during simple processing, low cost, and production runs. It has been found that it is necessary to produce a polytrimethylene terephthalate composition which simultaneously has properties such as ductility, low elongation at break and high flex recovery.

Disclosed herein is a monofilament bristle made of a modified polytrimethylene terephthalate composition, wherein the modified polytrimethylene terephthalate composition is based on the total weight of the modified polytrimethylene terephthalate composition.

(a) 85 to 95 weight percent of at least polytrimethylene terephthalate, and

(b) 5 to 15 weight percent of at least polyethylene-methyl acrylate copolymer,

The modified polytrimethylene terephthalate composition has a flexural modulus of 2500 MPa or less as measured according to ISO178: 2001, and a tensile modulus of 2600 MPa or less, respectively measured according to ISO527-2: 1993. Elongation at break is 20% or less.

Also disclosed is a brush comprising the monofilament bristles described herein immediately above.

In the present invention, it should be noted that when a range of values provides an upper end point and a lower end point of a particular value, the range includes any value within the endpoints, and a value that is equal to or nearly the same as the endpoints. .

Unless otherwise stated, all publications, patent applications, patents, and other references mentioned herein are incorporated herein by reference in their entirety, as if fully set forth herein.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as used by one of ordinary skill in the art. In case of conflict, the definitions herein will prevail.

Unless stated otherwise, all percentages, parts, ratios, etc., are by weight.

The present invention first discloses monofilament bristles made of a modified polytrimethylene terephthalate composition, wherein the modified polytrimethylene terephthalate composition is based on the total weight of the modified polytrimethylene terephthalate composition,

(a) about 85 to about 95 weight percent polytrimethylene terephthalate (PTT), and

(b) about 5 to about 15 weight percent of at least polyethylene-alkyl acrylate copolymer,

The modified polytrimethylene terephthalate composition has a flexural modulus of 2500 MPa or less, according to ISO178: 2001, a tensile modulus of 2600 MPa or less, and an elongation at break of 20% or less, respectively, measured according to ISO527-2: 1993. .

In one embodiment of the monofilament bristles, the modified polytrimethylene terephthalate composition is a single phase composition formed by at least polytrimethylene terephthalate and at least polyethylene-alkyl acrylate copolymer.

In another embodiment of the monofilament bristles, the modified polytrimethylene terephthalate composition has a flexural modulus measured according to ISO178: 2001 of 2000 to 2500 MPa and a tensile modulus of 2000 to 2600 measured according to ISO527-2: 1993, respectively. It is MPa and the elongation at break is 4 to 15%.

In another embodiment of the monofilament bristles, based on the total weight of the modified polytrimethylene terephthalate composition, at least the polytrimethylene terephthalate and at least the polyethylene-alkyl acrylate copolymers are preferably 86 to 92% by weight, respectively, and 8 to 14% by weight, or more preferably 87 to 89% by weight and 11 to 13% by weight, respectively.

In another embodiment of the monofilament bristles, at least the polyethylene-alkyl acrylate copolymers comprised in the modified polytrimethylene terephthalate composition are selected from one or more of polyethylene-alkyl (C ₁ -C ₁₀ ) acrylate copolymers or ; Preferably from polyethylene-methyl acrylate copolymers, polyethylene-ethyl acrylate copolymers, polyethylene-propyl acrylate copolymers, polyethylene-butyl acrylate copolymers, or combinations of two or more thereof.

In another embodiment of the monofilament bristles, at least the polytrimethylene terephthalate in the modified polytrimethylene terephthalate has an inherent viscosity of 0.8 to 1.7 dl / g, or preferably 0.9 to 1.4 dl / g.

In another aspect of the present invention, a brush comprising the monofilament bristles is provided. The brush selected may be a toothbrush, a paint brush, a cosmetic brush or an industrial brush. A preferred embodiment of the present invention is a toothbrush.

The polytrimethylene terephthalate used in the present invention may be a polyester obtained by condensation of 1,3-propylene glycol with terephthalic acid (or terephthalate). The 1,3-propylene glycols used in the preparation of polytrimethylene terephthalate can preferably be obtained via biochemical processes from renewable resources (1,3-propylene obtained via biochemical processes). One skilled in the art can select polytrimethylene terephthalate having a single intrinsic viscosity, or use several polytrimethylene terephthalates with different intrinsic viscosity simultaneously. Preferably, at least the polytrimethylene terephthalate used in the present invention has an intrinsic viscosity of about 0.8 to 1.7 dl / g, preferably about 0.9 to 1.4 dl / g.

Preferred polytrimethylene terephthalates are E.I. Manufactured by DU DuPont de Nemours and Company, USA, commercially available as Soron® (hereinafter referred to as DuPont) and having an intrinsic viscosity of 0.96 dl / g polytrimethylene terephthalate. The raw material 1,3-propylene used to prepare Sorona® polytrimethylene terephthalate is obtained through fermentation of corn sugar. Therefore, 37% of the starting materials for the polymer can come from natural renewable resources rather than traditional petrochemical feedstocks, thereby reducing the dependence on mineral and fossil resources.

Polyethylene-alkyl acrylate copolymers used in the present invention refer to such copolymers obtained from copolymerization of ethylene and alkyl acrylates, wherein the main chain is derived from polymerization of alkyl acrylate monomers and repeating units derived from polymerization of ethylene monomers. It includes repeating units. The alkyl group in the alkyl acrylate is a straight or branched C _1-10 alkyl group, preferably a straight or branched C _1-4 alkyl group, for example methyl, ethyl, n-propyl, iso-propyl, n-butyl, May be iso-butyl or tert-butyl. In one embodiment, the polyethylene-alkyl acrylate copolymer used is selected from polyethylene-methyl acrylate copolymers, polyethylene-ethyl acrylate copolymers, polyethylene-butyl acrylate copolymers and optional combinations thereof. In another embodiment, the polyethylene-alkyl acrylate copolymer used is selected from polyethylene-methyl acrylate copolymers.

In the present invention, based on the total weight of the polyethylene-alkyl acrylate copolymer, the alkyl acrylate monomer units are preferably about 4 to 40% by weight, more preferably about 8 to 35% by weight, most preferably about It is present in an amount of 18 to 30% by weight.

Polyethylene-alkyl acrylate copolymers used in the present invention are commercially available polyethylene copolymers manufactured by DuPont, USA and sold under Elvaloyl® AC, or ExxonMobil Chemical Company. It can be selected from commercially available polyethylene-methyl acrylate resins prepared by and marketed by Opthema ™.

Methods of making polyethylene-alkyl acrylate copolymers are known in the art. See, for example, Modern Plastics Encyclopedia and the Wiley Encyclopedia of Packaging Technology.

In the present invention, based on the total weight of the modified polytrimethylene terephthalate composition, the polytrimethylene terephthalate is about 85 to 95% by weight, preferably about 86 to 92% by weight, more preferably about 87 to 89 Present in weight percent. Based on the total weight of the modified polytrimethylene terephthalate composition, the polyethylene-alkyl acrylate copolymer is about 5 to 15 wt%, preferably about 8 to 14 wt%, more preferably about 11 to 13 wt% Exists in the amount of.

In the present invention, the modified polytrimethylene terephthalate has a flexural modulus measured according to ISO178: 2001 of about 2000 to 2500 MPa; The tensile modulus measured according to ISO527-2: 1993 is about 2000 to 2600 MPa and the percent elongation at break is about 4 to 15% or less.

In order to lower the flexural and tensile modulus of the material, a ductile material will probably be added. As a result, since the flexural modulus and the tensile modulus are lowered by the addition of the soft material, it can usually be expected that the percent elongation at break will increase accordingly. However, the inventors have surprisingly found that the modified polytrimethylene terephthalate of the present invention has a flexural modulus of about 2500 MPa or less, a tensile modulus of about 2600 MPa or less, and a percent elongation at break of about 20% or less. . That is, after addition of the copolymer of polyethylene-alkyl acrylate, the flexural modulus and tensile modulus decrease after the addition of the copolymer of polytrimethylene terephthalate alone, but the percent elongation at break remains basically the same or even decreases.

On the one hand, during the process of adding the soft material to the polyester material, the problem of incompatibility between the two materials usually occurs. If the two materials have poor compatibility, they can each be present in two phases, which can worsen the processability of the material, which in turn reduces the formability and durability of the product, or further extrusion Will affect the radiation directly. Surprisingly, the polytrimethylene terephthalate and polyethylene-alkyl acrylate copolymer in the modified polytrimethylene terephthalate composition of the monofilament bristles of the present invention can form a homogeneous single phase or single phase, and when extruded from an extruder, It was found that the molding processability was excellent. Such single phase compositions also have advantages such as being resistant to cracking and maintaining sufficient stability in thermal deformation and hygroscopic expansion even after prolonged use. Thus, the durability of the finished product, such as a toothbrush, paint brush, cosmetic brush, and the like is increased.

In the present invention, the term "single phase" or "single phase" means that the two materials are joined together without a clear phase interface between them under a microscope, or after these materials are mechanically extruded, the cross section and appearance of the materials may be any It is said that it is homogeneous without obvious exfoliation and phase interface, and cannot be separated by conventional techniques such as by mechanical separation.

Optionally, the compositions of the present invention may comprise small amounts of existing additives commonly used and well known in the polymer art. Examples of additives include, without limitation, antioxidants, heat stabilizers, UV stabilizers, colorants including dyes and pigments, lubricants, hydrolysis inhibitors and flame retardants. These additives in the composition are usually in amounts of about 0.01 to 15% by weight, preferably about 0.01 to 10% by weight, provided they do not reduce or impair the basic and novel properties of the composition and do not adversely affect the properties of the composition. Exists as.

There is no particular limitation on the manufacturing process of the monofilament bristle of the present invention. This may be any known polymer blending method in the art, which includes a solution extrusion spinning process and a melt extrusion spinning process, but is preferably a melt extrusion spinning process. For example, the monofilament bristles of the present invention can be prepared through the following process: after polytrimethylene terephthalate, polyethylene-alkyl acrylate copolymer, and other optional existing additives are melt-extruded by an extruder , Monofilament bristles can be obtained through drawing and shaping, wherein the extrusion temperature can be set to about 235 to 290 ° C., preferably about 245 to 265 ° C., and the extrusion rate can be about 200 to 400 rpm The throughput may be about 15 to 30 kg / hr.

The monofilament bristles of the present invention can be used in various fields according to different applications. In a preferred embodiment, monofilament bristles refer to monofilament bristles for use in toothbrushes, paint brushes, cosmetic brushes, or industrial brushes.

The invention also provides a brush comprising the monofilament bristles of the invention. Preferably, the brush of the present invention is a toothbrush, a paint brush or a cosmetic brush. If desired, the toothbrush, paint brush, cosmetic brush or industrial brush may comprise at least one bundle of monofilament bristles of the invention, wherein one bundle of monofilament bristles comprises at least one monofilament bristle of the invention And more preferably comprises several bundles of the monofilament bristles of the invention.

In the case of a toothbrush, paint brush, or cosmetic brush, the monofilament bristles of the present invention can be used alone or in combination with other monofilament bristles or fibers comprising other components, wherein the other components are polyamide , Polyethylene terephthalate (PET) or polybutylene terephthalate (PBT) and the like.

In another preferred embodiment, the brush of the invention is a toothbrush comprising at least one bundle of the monofilament bristle of the invention, preferably comprising several bundles of the monofilament bristle of the invention. More preferably, the monofilament bristle used in the toothbrush consists essentially of or consists entirely of the monofilament bristle of the present invention.

Example:

The invention is further illustrated by the following examples; The scope of the present invention is not limited by these specific embodiments included herein. Unless stated otherwise, all ratios and percentages in this application are by weight.

The materials used in the examples are as follows:

PTT: polytrimethylene terephthalate resin manufactured by DuPont USA and sold by Sorona® polytrimethylene terephthalate resin, having an intrinsic viscosity of 0.96 dl / g;

EMA: Polyethylene-methyl acrylate copolymer resin (comprising 24% by weight of methyl acrylate) manufactured by DuPont, USA and marketed by Elvaloyl® AC12024.

Comparative Example 1 and Comparative Example 2 and Examples 1 to 5

In each of Comparative Examples 1 and 2 and Examples 1 to 5, the ZSK26 twin screw extruder (with the temperature set to 230 to 255 ° C, the extrusion speed to 350 rpm, and the throughput set to 25 kg / hr) Purchased from the German company Coperion WP, appropriate amounts of PTT and EMA (weight ratios of each component listed in Table 1) are dried, preblended and melt-blended to obtain the desired composition. Got it.

The trimethylene terephthalate compositions used for Comparative Examples 1 and 2 and Examples 1-5 were injected into dumbbell-shaped test specimens. Dumbbell-shaped test specimens were molded. Flexural modulus is measured according to ISO178: 2001; Tensile strength, tensile modulus and percent elongation at break were measured according to ISO527-2: 1993.

The test results are listed in Table 1.

Table 1 shows that as the content of EMA in the compositions used in Examples 1-5 increases, flexural modulus and tensile modulus decrease. Surprisingly, the percent elongation at break does not correspondingly increase, but remains essentially the same (Examples 2 and 4), or slightly increases (Example 1), or even decreases (Examples 3 and 4). Example 5).

The above detailed embodiments are provided for the purpose of illustrating the present invention. It should not be understood to limit the scope of the invention in any way.

Claims (12)

A monofilament bristle made of a modified polytrimethylene terephthalate composition, wherein the modified polytrimethylene terephthalate composition is based on the total weight of the modified polytrimethylene terephthalate composition
(a) 85 to 95 weight percent of at least polytrimethylene terephthalate, and
(b) 5 to 15 weight percent of at least polyethylene-methyl acrylate copolymer,
The modified polytrimethylene terephthalate composition has a flexural modulus of 2500 MPa or less as measured according to ISO178: 2001, and a tensile modulus of 2600 MPa or less, respectively measured according to ISO527-2: 1993. Monofilament bristle with an elongation at break of 20% or less. The monofilament bristle of claim 1 wherein the modified polytrimethylene terephthalate composition is a single phase composition formed by at least polytrimethylene terephthalate and at least a polyethylene-alkyl acrylate copolymer. The monofilament bristle according to claim 1 or 2, wherein the modified polytrimethylene terephthalate composition has a flexural modulus of 2000 to 2500 MPa, a tensile modulus of 2000 to 2600 MPa, and a percent elongation at break of 4 to 15%. The method of claim 3, wherein, based on the total weight of the modified polytrimethylene terephthalate composition, at least polytrimethylene terephthalate is present in an amount of from 86 to 92 weight percent, and at least the polyethylene-alkyl acrylate copolymer is from 8 to 14% by weight monofilament bristle. The method of claim 4, wherein, based on the total weight of the modified polytrimethylene terephthalate composition, at least polytrimethylene terephthalate is present in an amount of 87 to 89 weight percent, and at least the polyethylene-alkyl acrylate copolymer is 11 to 13% by weight monofilament bristle. The monofilament bristle of claim 5 wherein at least the polyethylene-alkyl acrylate copolymer is selected from one or more polyethylene-alkyl (C _1-10 ) acrylate copolymers. The method of claim 6, wherein at least the polyethylene-alkyl acrylate copolymer is a polyethylene-methyl acrylate copolymer, polyethylene-ethyl acrylate copolymer, polyethylene-propyl acrylate copolymer, polyethylene-butyl acrylate copolymer, or one or more Monofilament bristles selected from combinations thereof. 8. The monofilament bristle of claim 7, wherein at least the polyethylene-alkyl acrylate copolymer is selected from polyethylene-methyl acrylate copolymers. 8. The monofilament bristle of claim 7, wherein at least the polytrimethylene terephthalate has an intrinsic viscosity of 0.8 to 1.7 dl / g, or preferably 0.9 to 1.4 dl / g. A brush comprising the monofilament bristle according to claim 1. The brush of claim 10 selected from toothbrushes, paint brushes, cosmetic brushes or industrial brushes. 12. The brush of claim 11 which is a toothbrush.