CN115105623B - Hydrocolloid repairing application with low adhesive liquid absorption and residual adhesive and preparation method thereof - Google Patents

Abstract

The invention discloses a hydrocolloid repairing application with low viscous liquid absorption and residual gum and a preparation method thereof, which are based on the influence of a molecular structure on material performance, carry out a great deal of researches on elastic hot melt adhesives, determine the most suitable elastic hot melt adhesives and radically solve the mechanical problem of the hydrocolloid; the formula of the invention simultaneously comprises water-soluble high molecular substances and water-swelling high molecular compounds, and when the hydrocolloid is applied and stuck on a wound, the hydrocolloid layer can provide excellent adhesion due to the synergistic effect of various molecules, can be torn off and absorb exudates in a whole piece, prevents bacteria from breeding, avoids wound infection and is beneficial to wound healing.

Description

A viscous, liquid-absorbing, low-residual hydrocolloid repair dressing and its preparation method

Technical field

The invention belongs to the field of medical dressings, and specifically relates to a viscous, liquid-absorbing, low-residual hydrocolloid repair dressing and a preparation method thereof.

Background technique

Hydrocolloid dressing is a new type of wound repair medical material made by mixing particles of hydrophilic polymer substances and hot-melt pressure-sensitive adhesive. It has the water-absorbing properties of hydrophilic polymers and the adhesive properties of rubber. It is mainly used for skin diseases. It has good curative effect on medical and surgical wounds, and has good curative effect on ostomies, bedsores, and infectious ulcers. This type of dressing can absorb a small to medium amount of exudate, and its airtightness can block the invasion of microorganisms, provide a moist environment for wound healing, and at the same time play a partial debridement effect.

However, the existing hydrocolloid dressing has a small amount of liquid absorption and cannot completely absorb wound exudate; on the other hand, the dressing integrity is poor and the viscosity is significantly reduced after liquid absorption, and it is easy to slip and adhere with the movement of the skin. The time is short, and these factors have caused an increase in the cost of medical treatment for patients.

Therefore, improving the integrity of the hydrocolloid enables the entire piece to be peeled off, increasing the viscosity of the hydrocolloid reduces the frequency of replacement, improves the hydrocolloid's liquid absorption capacity, absorbs exudate and secreted sweat from the wound, guides the normal discharge of pus from the body, and accelerates the wound Healing is of great significance to wound care.

Contents of the invention

In order to solve the above-mentioned defects in the prior art, the present invention provides a hydrocolloid repair dressing with viscous liquid absorption and low residual glue and a preparation method thereof.

This invention adopts a method different from the traditional research method on the performance of dressing materials. Instead, it conducts a large number of experimental studies based on the influence of molecular structure on material properties to solve the mechanical problems of hydrocolloids from the root cause. When the proposed hydrocolloid patch is pasted on a wound, due to the synergistic effect of multiple molecules, its hydrocolloid layer can provide excellent adhesion, and can be peeled off and absorb exudate in its entirety to prevent bacterial growth and avoid wounds. infection, which is beneficial to wound healing.

The technical solution of the present invention is as follows:

A viscous, liquid-absorbent, low-residual hydrocolloid repair application consists of an anti-adhesive layer, a hydrocolloid layer, and a backing layer. The hydrocolloid layer is located between the anti-adhesive layer and the backing layer;

Wherein, the hydrocolloid layer consists of the following components by weight:

Preferably, the hydrocolloid layer consists of the following components by weight:

In the hydrocolloid layer of the present invention, the elastic hot melt adhesive can be one or more of the styrene elastic hot melt adhesives, such as: SIS (styrene-isoprene-styrene block copolymer) , SBS (styrene-butadiene-styrene block copolymer), SBS and SIS modified elastomers SEBS, SEPS, etc. The preferred ones are the SIS series of polyisoprene block copolymers with multiple methyl side chains. The more preferred ones are those with a star-shaped rubber structure, large molecular weight (>100,000), and high styrene content (10 ~40%), a styrenic elastic hot melt adhesive with a moderate content of SI diblock polymer (10~50%) and high cohesion, which can be made into ultra-thin hydrocolloids. For example, SIS hot melt adhesive RT-7031 contains a star-shaped rubber structure, a molecular weight of 100,000 to 150,000, a styrene content of 29 to 34%, and an SI diblock content of 15% to 44%.

In the hydrocolloid layer of the present invention, the hydrophilic polymer substance is a combination of a water-soluble polymer substance and a water-absorbing swellable polymer substance. Among them, the water-soluble polymer material can be selected from plant gum, animal gum, natural starch, chitin, alginic acid and its derivatives, sodium carboxymethyl cellulose (CMC), cationic starch, polyethylene glycol, polyvinyl alcohol , one or more of polyvinylpyrrolidone, etc. The water-absorbing swelling polymer material can be selected from croscarmellose sodium (X-CMC), cross-linked polyvinylpyrrolidone (PVPP), carboxymethyl starch (CMS), low-substituted hydroxypropyl cellulose (L- HPC), etc. One or more. Water-soluble polymer substances are easily soluble in water. After absorbing water, they are easily leached from the rubber phase and remain on the skin, reducing the integrity of the dressing. It is easy to break after absorbing wound exudate. Water-absorbing swelling polymer materials have the property of swelling by absorbing water but being insoluble in water. During the swelling process, the particles form a gel-like structure, and the macromolecules are fixed in the gel network composed of cross-linked hydrocolloids and are not easily removed from the rubber network. Leaching can improve the integrity of hydrocolloids. The present invention preferably uses a mixture of water-soluble and water-absorbing swellable polymer materials, such as sodium carboxymethylcellulose and croscarmellose sodium.

In the hydrocolloid layer of the present invention, the bacteriostatic agent is a polycationic polymer material, such as chitosan, which has extremely strong antibacterial properties and is also water absorbent. It is combined with polyanionic cellulose ether (CMC) , reduce the leaching of CMC from the rubber phase after absorbing water, reduce skin residue, and improve the integrity of the dressing.

In the hydrocolloid layer of the present invention, the tackifying resin is selected from thermoplastic resins that are compatible with both the hard plastic phase and the soft rubber phase in the styrenic thermoplastic elastomer, and can be natural resin, terpene resin, petroleum resin One or more of the series, preferably rosin resin, has a molecular weight of 200 to 1500, and a softening point generally between 70 and 150°C to improve the adhesive strength. Such as hydrogenated rosin resin 201 (softening point 90°C), hydrogenated pentaerythritol rosin resin 203 (softening point 100°C).

In the hydrocolloid layer of the present invention, the plasticizer can be one or more of liquid paraffin, white oil, and naphthenic oil series to improve adhesion, increase initial viscosity, and reduce melt viscosity and cost. The lower the dissolution parameter and the higher the molecular weight of mineral oil, Mr≥500, viscosity≥200mm ² /s, the more incompatible it is with the plastic phase, the smaller the impact on the cohesive strength of the hot-melt pressure-sensitive adhesive, and the greater the softening effect. good. If the mineral oil contains aromatic hydrocarbons, it will reduce the bonding strength at room temperature or high temperature. Preferred are naphthenic oils, such as naphthenic oil 600 and naphthenic oil 400.

The anti-adhesive layer of the present invention is used to protect the hydrocolloid layer and facilitate peeling. The material of the anti-adhesive layer is such as: silicone-coated glassine paper release paper, or silicone-coated polyethylene, polyethylene terephthalate, polyvinyl chloride, polyester plasma release film.

One side of the backing layer of the present invention is firmly adhered to the hydrocolloid layer, and the other side has no stickiness. The materials of the backing layer include: non-woven fabric, polyvinyl chloride film, polyethylene film, polyethylene terephthalate film, polyurethane film, etc.

The preparation method of the viscous, liquid-absorbing and low-residual hydrocolloid repair dressing of the present invention is:

Melt and mix the elastic hot melt adhesive and plasticizer at 150-190°C for 5-20 minutes, and then add the formula amount of tackifying resin, bacteriostatic agent, and Water-soluble polymer substances and water-absorbing expandable polymer substances are mixed for 5 to 20 minutes, supplemented by vacuum conditions, to remove bubbles generated during the stirring process. After the glue is fully mixed, apply it on the backing layer and cover it with waterproof After the adhesive layer is formed, vulcanize and press flat plate for 1 to 10 minutes at 70 to 110°C (slightly higher than the softening point) and 0.5 MPa to form a 150 to 1000 μm (preferably 200 to 500 μm) hydrocolloid layer to obtain the viscosity. Hydrocolloid repair dressing with liquid absorption and low adhesive residue.

This invention adopts a method different from the traditional research method on the performance of dressing materials. Instead, it conducts a large number of in-depth experimental studies based on the influence of molecular structure on material properties to solve the mechanical problems of hydrocolloids from the root cause. Due to the synergistic effect of multiple molecules, the beneficial effects are as follows:

a. The hydrocolloid patch of the present invention has good integrity after absorbing liquid, can be peeled off in its entirety, leaving no residual glue, and is convenient for wound treatment.

b. The hydrocolloid patch of the present invention not only gives the dressing the ability to absorb exudate, but does not significantly affect the stickiness of the skin around the wound, so that the patch can be firmly fixed at the wound location and facilitate physical activities.

c. The hydrocolloid application of the present invention is light and thin, has a color similar to that of the skin, has good aesthetics after application, and has an invisible effect.

d. The hydrocolloid patch of the present invention is simple to make, has low production cost, and is suitable for large-scale application.

Detailed ways

The principles and features of the present invention are described below with examples. The examples are only used to explain the present invention and are not intended to limit the scope of the present invention.

The test methods for the performance indicators used in the embodiments are as follows:

Water absorption test: Prepare test solution A composed of sodium chloride and calcium chloride. This solution contains 142mmol/L sodium ions and 2.5mmol/L calcium ions. Its ion content is equivalent to human serum or wound exudate. The preparation method is: dissolve 8.298g sodium chloride and 0.277g calcium chloride in a volumetric flask with deionized water and dilute to 1L.

The hydrocolloid dressing to be tested was pressed into a sheet with a thickness of 0.5 mm, a circular test piece with a diameter of 30 mm was punched out, and one side of the test piece was covered with a polyurethane film. Weigh the sample, and measure the mass before the test to be m ₁ . Put it into the test solution A at (37±1)°C. Its mass is 40 times ±0.5g of the sample. After 24 hours, take out the sample and clamp it with tweezers. Hold one corner of the sample and hang it in the air for 30 seconds, and weigh it again to obtain the mass of the water-absorbing sample, which is m ₂ . Record the increase in weight as the amount of water absorbed.

Water absorption (g/m ² /24h) = 4 (m ₂ -m ₁ )/(π×32×10 ^-4 )

Integrity test: Press the hydrocolloid dressing to be tested into a sheet with a thickness of 0.5mm, punch out a circular test piece with a diameter of 30mm, and cover one side of the test piece with a polyurethane film. Weigh the sample and measure the mass before the test as m ₁ . Put 150ml of test solution A into a 250ml conical flask, put the sample in, seal the bottle mouth and put it into the thermostat. The thermostat temperature is set to 37°C. Keeping the experimental conditions unchanged, take out the sample after 24 hours, place it in a blast drying oven, dry it at 60°C for 24 hours, and then weigh the dried sample mass as m ₂ .

Completeness=m ₂ /m ₁ ×100%

Peel strength test: Place the sample on the center of the clean surface of the stainless steel so that both sides of the sample are parallel to the two long sides of the steel plate. Use a roller to apply pressure to the pasted part of the sample and roll it four times along the length of the sample at a speed of about 60cm/min. A suitable force measuring instrument with a force value reading range between 15% and 85% of the full scale is used to measure the force required to peel off the sample from the steel plate (force application angle is 180°, peeling speed is 270mm/min~330mm/min ). Observe the force applied at the first 25mm length, observe the force every 30mm, and take the average of the six readings.

In the following examples, RT-7031 hot melt adhesive, RT-7019 hot melt adhesive, and RT-7035 hot melt adhesive were purchased from Shanghai Shisheng Technology Co., Ltd.

Example 1

In parts by weight, 32.0g Rheotac RT-7031 hot melt adhesive (containing star-shaped rubber structure, molecular weight 100,000-150,000, styrene content 29-34%, SI diblock content 15%-44%; used below Same as RT-7031 hot melt glue), 2.5g naphthenic oil 600, heat it in an oil bath at 175°C to melt it; add 1.5g chitosan, stir to make the chitosan evenly dispersed in the glue; add 18.0 in batches g CMC, stir while adding, until the glue solution is evenly mixed, and after vacuum degassing, apply it on the backing layer, cover it with an anti-adhesive layer, and press it with a flat vulcanizer at 90°C and 0.5MPa for 10 minutes to obtain 500μm thick hydrocolloid. The hydrocolloid dressing of this formula has a water absorption of 2220g/m ² /24h, an integrity of 86.2%, and a peel strength of 4.18N/cm.

Example 2

In parts by weight, 25.0g Rheotac RT-7019 hot melt adhesive (linear rubber structure, molecular weight 100,000-150,000, styrene content 14-15%, SI diblock content 14%-44%; RT- used below 7019 hot melt adhesive), 6.0g naphthenic oil 400, heat it in an oil bath at 160°C to melt it; add 1.5g chitosan, stir to make the chitosan evenly dispersed in the glue; add 16.5g CMC in batches , stir while adding, until the glue solution is evenly mixed, and after vacuum degassing, apply it on the backing layer, cover it with an anti-adhesive layer, and press it with a flat vulcanizer at 70°C and 0.5MPa for 10 minutes to obtain a thickness of 500 μm. of hydrocolloids. The hydrocolloid dressing with this formula has a water absorption of 2679g/m ² /24h, an integrity of 90.12%, and a peel strength of 2.51N/cm.

Example 3

In parts by weight, heat 32.0g RT-7019 hot melt glue and 2.5g naphthenic oil 600 in an oil bath at 160°C to melt them; add 2.5g chitosan and stir to make the chitosan evenly dispersed in the glue; Add 18.0g CMC in batches, stir while adding, until the glue is evenly mixed, apply it on the backing layer, cover it with an anti-adhesive layer, and press it with a flat vulcanizer at 70°C and 0.5MPa for 10 minutes to get 500μm Thickness of hydrocolloid. The hydrocolloid dressing of this formula has a water absorption of 2327g/m ² /24h, an integrity of 85.78%, and a peel strength of 2.89N/cm.

Example 4

In parts by weight, 32.0g Rheotac RT-7035 (linear rubber structure, molecular weight 100,000-140,000, styrene content 15-34%, SI diblock content 25%-34%), 2.5g naphthenic oil 600 were added. Heat in an oil bath at 175°C to melt it; add 2.5g chitosan and stir to make the chitosan evenly dispersed in the glue; add 18.0g CMC in batches, stir while adding, until the glue is evenly mixed, and coat On the backing layer, cover it with an anti-adhesive layer, and press it with a flat vulcanizer at 110°C and 0.5MPa for 10 minutes to obtain a hydrocolloid with a thickness of 500 μm. The hydrocolloid dressing with this formula has a water absorption of 2321g/m ² /24h, an integrity of 86.78%, and a peel strength of 3.51N/cm.

Example 5

In parts by weight, heat 32.0g RT-7031 hot melt glue and 2.5g naphthenic oil 400 in an oil bath at 175°C to melt them; add 2.5g chitosan and stir to make the chitosan evenly dispersed in the glue. ;Add 18.0g CMC in batches, stir while adding, until the glue is evenly mixed, apply it on the backing layer, cover it with an anti-adhesive layer, and press it with a flat vulcanizer for 5 minutes at 110°C and 0.5MPa to get the result 500μm thick hydrocolloid. The hydrocolloid dressing with this formula has a water absorption of 1359.96g/m ² /24h, an integrity of 89.56%, and a peel strength of 2.46N/cm.

Example 6

In parts by weight, put 32.0g RT-7031 hot melt adhesive and 2.0g naphthenic oil 600 into a beaker, use an oil bath at 175°C to melt them, add 1.5g rosin 201, and stir to make the rosin 201 evenly dispersed in the melt. into the glue; add 2.5g chitosan and stir to make the chitosan evenly dispersed in the glue; add 32.0g CMC in batches, stirring while adding, until the glue is evenly mixed, apply it on the backing layer, and cover it with anti- The adhesive layer is pressed with a flat vulcanizer at 110°C and 0.5MPa for 5 minutes to obtain a hydrocolloid with a thickness of 500 μm. The hydrocolloid dressing of this formula has a water absorption of 4506g/m ² /24h, an integrity of 76.3%, and a peel strength of 4.56N/cm.

Example 7

In parts by weight, put 32.0g RT-7031 hot melt adhesive and 2.0g naphthenic oil 600 into a beaker, use an oil bath at 175°C to melt them, add 1.5g rosin 201, and stir to make the rosin 201 evenly dispersed in the melt. In the glue; add 2.5g chitosan, stir to make the chitosan evenly dispersed in the glue; add 12.0g CMC, 20.0g X-CMC in batches, stir while adding, until the glue is evenly mixed, apply it to the backing layer, covered with an anti-adhesive layer, and pressed with a flat vulcanizer for 5 minutes at 110°C and 0.5MPa to obtain a hydrocolloid with a thickness of 500 μm. The hydrocolloid dressing of this formula has a water absorption of 5557g/m ² /24h, an integrity of 88.3%, and a peel strength of 5.47N/cm.

Example 8

In parts by weight, put 32.0g RT-7031 hot melt adhesive and 2.0g naphthenic oil 600 into a beaker, use an oil bath at 175°C to melt them, add 1.5g rosin 201, and stir to make the rosin 201 evenly dispersed in the melt. In the glue; add 2.5g chitosan, stir to make the chitosan evenly dispersed in the glue; add 32.0g X-CMC in batches, stir while adding, until the glue is evenly mixed, apply it on the backing layer, top Cover with an anti-adhesive layer and press it with a flat vulcanizer for 5 minutes at 110°C and 0.5MPa to obtain a hydrocolloid with a thickness of 500 μm. The hydrocolloid dressing of this formula has a water absorption of 5353g/m ² /24h, an integrity of 77.8%, and a peel strength of 5.13N/cm.

Example 9

In parts by weight, put 32.0g RT-7031 hot melt adhesive and 5.0g naphthenic oil 600 into a beaker, use an oil bath at 175°C to melt them, add 5.0g rosin 201, stir to make the rosin 201 evenly dispersed in the molten In the glue; add 2.5g chitosan, stir to make the chitosan evenly dispersed in the glue; add 12.0g CMC, 20.0g X-CMC in batches, stir while adding, until the glue is evenly mixed, apply it to the backing layer, covered with an anti-adhesive layer, and pressed with a flat vulcanizer for 10 minutes at 110°C and 0.5MPa to obtain a hydrocolloid with a thickness of 500 μm. The hydrocolloid dressing with this formula has a water absorption of 4826g/m ² /24h, an integrity of 92.2%, and a peel strength of 6.26N/cm.

It can be seen from the examples that the structure of the hot melt adhesive significantly affects the viscosity and integrity of the hydrocolloid application. The hot melt adhesive containing a star-shaped rubber structure and a higher styrene content has stronger cohesion and better adhesion; the ring with high viscosity Alkane oil, its viscosity will also be better; the content of hydrophilic polymers is high, and it has strong binding force with water molecules. The hydrocolloid dressing has strong water absorption, but poor integrity; by adjusting the content ratio of CMC, X-CMC and chitosan Within the appropriate range, the negatively charged groups of CMC and CMC particles absorb water and swell to form a gel-like structure, which is intertwined with the hot melt adhesive macromolecules. The water-soluble molecules are fixed in the network of hydrocolloids and are not easily leached from the gel network, reducing the hydrophilic polymers from the rubber phase after absorbing water. Leach out and remain on the skin, improving the integrity of the dressing. The hydrocolloid patch of the present invention absorbs a large amount of liquid, has good integrity after absorbing liquid, leaves no residual glue, and is convenient for wound treatment; the patch has strong stickiness and can be firmly fixed at the wound location, making it convenient for body activities.

Claims (4)

1. A viscous, liquid-absorbing and low-residual hydrocolloid repair application, which is characterized in that it consists of an anti-adhesive layer, a hydrocolloid layer, and a backing layer, and the hydrocolloid layer is located between the anti-adhesive layer and the backing layer; The hydrocolloid layer is composed of the following components by weight: in, The elastic hot melt adhesive is a styrenic elastic hot melt adhesive with a star-shaped rubber structure, a molecular weight >100,000, a styrene content of 10-40%, and an SI diblock polymer content of 10-50%; The water-soluble polymer substance is sodium carboxymethyl cellulose; The water-absorbing swelling polymer material is croscarmellose sodium; The bacteriostatic agent is chitosan. 2. The viscous, liquid-absorbing, low-residual hydrocolloid repair application as claimed in claim 1, wherein the tackifying resin is selected from one or more of natural resins, terpene resins, and petroleum resins. 3. The viscous, liquid-absorbing, low-residual hydrocolloid repair application as claimed in claim 1, wherein the plasticizer is selected from one or more of liquid paraffin, white oil, and naphthenic oil. 4. A method for preparing a viscous, liquid-absorbing and low-residual hydrocolloid repair dressing as claimed in claim 1, characterized in that the preparation method is: Melt and mix the elastic hot melt adhesive and plasticizer at 150-190°C for 5-20 minutes, and then add the formula amount of tackifying resin, bacteriostatic agent, and Water-soluble polymer substances and water-absorbing expandable polymer substances are mixed for 5 to 20 minutes, supplemented by vacuum conditions, to remove bubbles generated during the stirring process. After the glue is fully mixed, apply it on the backing layer and cover it with waterproof After the layer is adhered, the flat plate is vulcanized and pressed for 1 to 10 minutes at 70 to 110°C and 0.5 MPa to form a 150 to 1000 μm thick hydrocolloid layer, thereby obtaining the viscous, liquid-absorbing and low-residual hydrocolloid repair dressing.