エチルセルロース 化学特性,用途語,生産方法
外観
白色〜わずかにうすい褐色, 顆粒
定義
本品は、セルロース(*)のエチルエーテルである。参照表示名称：セルロース
溶解性
水に可溶。多くの有機溶剤に可溶。エタノールに溶け、水にほとんど溶けない。
解説
エチルセルロース,セルロースのヒドロキシ基をエチルエーテル化したもの．アルカリセルロースに硫酸ジエチルまたは塩化エチルなどのエチル化剤を一般に不均一系で反応させる．グルコース単位当たり3個あるヒドロキシ基のうち，エーテル化されたものの数で表す置換度により，溶解性，軟化温度などの諸性質が異なる．低置換度(0.8以下)のものはアルカリに可溶，置換度0.8～1.3のものは水溶性で，高置換度になるにつれて，アルコールなどの極性溶媒や無極性溶媒に可溶になり，置換度2.4～2.5において他種類の溶媒に可溶となる．この溶媒可溶性，ほかの樹脂との相溶性，安定性，耐水性，耐薬品性にすぐれることから，塗料，プラスチック，フィルムなどに広く利用されている．
用途
エチルセルロース,セルロース誘導体の一種で，プラスチック，ラッカー，ワニス，接着剤，透明シートに使われている。広い温度にわたって強度と可撓性を保持する熱可塑性プラスチックであり，押出成形や射出成形で成形される。コットンリンターや木材パルプを水酸化ナトリウムと反応させてアルカリセルロースとし，その水酸基を塩化エチルによってエーテル化して作る。置換度によって諸性質が異なり，高置換度になるにつれて多種類の溶媒に可溶となる。
化粧品の成分用途
結合剤、皮膜形成剤、親水性増粘剤、香料
化学的特性
white to slightly yellowish powder
化学的特性
Ethyl celluloses are low density polymers (1070–1180 kg.m–3) with solubilities depending on the degree of ethylation; usually commercial grade contains 44–48% ethoxyl functional groups. Solid masses of ethylcellulose exhibit low absorption of moisture, excellent dimensional stability and low temperature toughness and impact resistance. Chemically they are less resistant towards acids than cellulose esters but much more resistant to alkalis. They can be processed by injection molding. Because ethylcellulose is soluble in a wide variety of solvents, it provides a wide variety of varnish formulations. Benzylcelluloses yield plastics with excellent dielectric properties and chemical stability.
使用
ethyl cellulose is a binder, film former, and thickener. It is used in suntan gels, creams, and lotions. This is the ethyl ether of cellulose.
調製方法
Ethylcellulose is prepared by treating purified cellulose (sourced
from chemical-grade cotton linters and wood pulp) with an alkaline
solution, followed by ethylation of the alkali cellulose with
chloroethane as shown below, where R represents the cellulose
radical:
RONa + C2H5Cl→ROC2H5+NaCl
The manner in which the ethyl group is added to cellulose can be
described by the degree of substitution (DS). The DS designates the
average number of hydroxyl positions on the anhydroglucose unit
that have been reacted with ethyl chloride. Since each anhydroglucose
unit of the cellulose molecule has three hydroxyl groups, the
maximum value for DS is three.
製造方法
Ethyl cellulose is prepared by reacting cellulose with caustic to form caustic cellulose, which is then reacted with chloroethane to form ethyl cellulose. Plasticgrade material contains 44-48% ethoxyl.
Although not as resistant as cellulose esters to acids, it is much more resistant to bases. An outstanding feature is its toughness at low temperatures.
安全性プロファイル
Low toxicity by
ingestion and skin contact. A skin irritant.
When heated to decomposition it emits
acrid smoke and irritating fumes
安全性
Ethylcellulose is widely used in oral and topical pharmaceutical
formulations. It is also used in food products. Ethylcellulose is not
metabolized following oral consumption and is therefore a
noncalorific substance. Because ethylcellulose is not metabolized it
is not recommended for parenteral products; parenteral use may be
harmful to the kidneys.
Ethylcellulose is generally regarded as a nontoxic, nonallergenic,
and nonirritating material.
As ethylcellulose is not considered to be a health hazard, the
WHO has not specified an acceptable daily intake. The highest
reported level used in an oral product is 308.8 mg in an oral
sustained release tablet.
LD50 (rabbit, skin): >5 g/kg
LD50 (rat, oral): >5 g/kg
貯蔵
Ethylcellulose is a stable, slightly hygroscopic material. It is
chemically resistant to alkalis, both dilute and concentrated, and
to salt solutions, although it is more sensitive to acidic materials
than are cellulose esters.
Ethylcellulose is subject to oxidative degradation in the presence
of sunlight or UV light at elevated temperatures. This may be
prevented by the use of antioxidant and chemical additives that
absorb light in the 230–340nm range.
Ethylcellulose should be stored at a temperature not exceeding
32°C (90°F) in a dry area away from all sources of heat. It should
not be stored next to peroxides or other oxidizing agents.
不和合性
Incompatible with paraffin wax and microcrystalline wax.
規制状況(Regulatory Status)
GRAS listed. Accepted for use as a food additive in Europe.
Included in the FDA Inactive Ingredients Database (oral capsules,
suspensions and tablets; topical emulsions and vaginal preparations).
Included in nonparenteral medicines licensed in Europe.
Included in the Canadian List of Acceptable Non-medicinal
Ingredients.
エチルセルロース 上流と下流の製品情報
原材料
準備製品